diff --git a/src/core/components/errors.jsx b/src/core/components/errors.jsx
index c72dd2fd..c3d6cf93 100644
--- a/src/core/components/errors.jsx
+++ b/src/core/components/errors.jsx
@@ -113,7 +113,7 @@ const SpecErrorItem = ( { error, jumpToLine } ) => {
   }
 
 function toTitleCase(str) {
-  return str
+  return (str || "")
     .split(" ")
     .map(substr => substr[0].toUpperCase() + substr.slice(1))
     .join(" ")
diff --git a/src/core/components/object-model.jsx b/src/core/components/object-model.jsx
index 9ab4e99a..db8adfd5 100644
--- a/src/core/components/object-model.jsx
+++ b/src/core/components/object-model.jsx
@@ -21,6 +21,10 @@ export default class ObjectModel extends Component {
     let { specSelectors } = otherProps
     let { isOAS3 } = specSelectors
 
+    if(!schema) {
+      return null
+    }
+
     let description = schema.get("description")
     let properties = schema.get("properties")
     let additionalProperties = schema.get("additionalProperties")
diff --git a/src/core/components/operation.jsx b/src/core/components/operation.jsx
index d1cc6786..457ee863 100644
--- a/src/core/components/operation.jsx
+++ b/src/core/components/operation.jsx
@@ -12,8 +12,10 @@ export default class Operation extends PureComponent {
     method: PropTypes.string.isRequired,
     operation: PropTypes.object.isRequired,
     showSummary: PropTypes.bool,
+    isShown: PropTypes.bool.isRequired,
 
-    isShownKey: CustomPropTypes.arrayOrString.isRequired,
+    tagKey: PropTypes.string,
+    operationKey: PropTypes.string,
     jumpToKey: CustomPropTypes.arrayOrString.isRequired,
 
     allowTryItOut: PropTypes.bool,
@@ -52,38 +54,16 @@ export default class Operation extends PureComponent {
   }
 
   componentWillReceiveProps(nextProps) {
-    const defaultContentType = "application/json"
-    let { specActions, path, method, operation } = nextProps
-    let producesValue = operation.get("produces_value")
-    let produces = operation.get("produces")
-    let consumes = operation.get("consumes")
-    let consumesValue = operation.get("consumes_value")
-
     if(nextProps.response !== this.props.response) {
       this.setState({ executeInProgress: false })
     }
-
-    if (producesValue === undefined) {
-      producesValue = produces && produces.size ? produces.first() : defaultContentType
-      specActions.changeProducesValue([path, method], producesValue)
-    }
-
-    if (consumesValue === undefined) {
-      consumesValue = consumes && consumes.size ? consumes.first() : defaultContentType
-      specActions.changeConsumesValue([path, method], consumesValue)
-    }
   }
 
   toggleShown =() => {
-    let { layoutActions, isShownKey } = this.props
-    layoutActions.show(isShownKey, !this.isShown())
-  }
+    let { layoutActions, tagKey, operationKey, isShown } = this.props
+    const isShownKey = ["operations", tagKey, operationKey]
 
-  isShown =() => {
-    let { layoutSelectors, isShownKey, getConfigs } = this.props
-    let { docExpansion } = getConfigs()
-
-    return layoutSelectors.isShown(isShownKey, docExpansion === "full" ) // Here is where we set the default
+    layoutActions.show(isShownKey, !isShown)
   }
 
   onTryoutClick =() => {
@@ -102,7 +82,9 @@ export default class Operation extends PureComponent {
 
   render() {
     let {
-      isShownKey,
+      operationKey,
+      tagKey,
+      isShown,
       jumpToKey,
       path,
       method,
@@ -156,18 +138,17 @@ export default class Operation extends PureComponent {
     }
 
     let { tryItOutEnabled } = this.state
-    let shown = this.isShown()
     let onChangeKey = [ path, method ] // Used to add values to _this_ operation ( indexed by path and method )
 
     return (
-        <div className={deprecated ? "opblock opblock-deprecated" : shown ? `opblock opblock-${method} is-open` : `opblock opblock-${method}`} id={isShownKey.join("-")} >
+        <div className={deprecated ? "opblock opblock-deprecated" : isShown ? `opblock opblock-${method} is-open` : `opblock opblock-${method}`} id={`operations-${tagKey}-${operationKey}`} >
           <div className={`opblock-summary opblock-summary-${method}`} onClick={this.toggleShown} >
               <span className="opblock-summary-method">{method.toUpperCase()}</span>
               <span className={ deprecated ? "opblock-summary-path__deprecated" : "opblock-summary-path" } >
               <a
                 className="nostyle"
                 onClick={isDeepLinkingEnabled ? (e) => e.preventDefault() : null}
-                href={isDeepLinkingEnabled ? `#/${isShownKey[1]}/${isShownKey[2]}` : null}>
+                href={isDeepLinkingEnabled ? `#/${tagKey}/${operationKey}` : null}>
                 <span>{path}</span>
               </a>
                 <JumpToPath path={jumpToKey} />
@@ -193,7 +174,7 @@ export default class Operation extends PureComponent {
             }
           </div>
 
-          <Collapse isOpened={shown}>
+          <Collapse isOpened={isShown}>
             <div className="opblock-body">
               { deprecated && <h4 className="opblock-title_normal"> Warning: Deprecated</h4>}
               { description &&
diff --git a/src/core/components/operations.jsx b/src/core/components/operations.jsx
index 6d760d53..b4958884 100644
--- a/src/core/components/operations.jsx
+++ b/src/core/components/operations.jsx
@@ -127,7 +127,8 @@ export default class Operations extends React.Component {
 
                         const operationId =
                         op.getIn(["operation", "operationId"]) || op.getIn(["operation", "__originalOperationId"]) || opId(op.get("operation"), path, method) || op.get("id")
-                        const isShownKey = ["operations", createDeepLinkPath(tag), createDeepLinkPath(operationId)]
+                        const tagKey = createDeepLinkPath(tag)
+                        const operationKey = createDeepLinkPath(operationId)
 
                         const allowTryItOut = specSelectors.allowTryItOutFor(op.get("path"), op.get("method"))
                         const response = specSelectors.responseFor(op.get("path"), op.get("method"))
@@ -135,11 +136,12 @@ export default class Operations extends React.Component {
 
                         return <Operation
                           {...op.toObject()}
-
-                          isShownKey={isShownKey}
+                          tagKey={tagKey}
+                          operationKey={operationKey}
+                          isShown={layoutSelectors.isShown(["operations", tagKey, operationKey])}
                           jumpToKey={jumpToKey}
                           showSummary={showSummary}
-                          key={isShownKey}
+                          key={tagKey + operationKey}
                           response={ response }
                           request={ request }
                           allowTryItOut={allowTryItOut}
diff --git a/src/core/plugins/err/actions.js b/src/core/plugins/err/actions.js
index d7051b74..40fd1121 100644
--- a/src/core/plugins/err/actions.js
+++ b/src/core/plugins/err/actions.js
@@ -3,6 +3,7 @@ import serializeError from "serialize-error"
 export const NEW_THROWN_ERR = "err_new_thrown_err"
 export const NEW_THROWN_ERR_BATCH = "err_new_thrown_err_batch"
 export const NEW_SPEC_ERR = "err_new_spec_err"
+export const NEW_SPEC_ERR_BATCH = "err_new_spec_err_batch"
 export const NEW_AUTH_ERR = "err_new_auth_err"
 export const CLEAR = "err_clear"
 
@@ -27,6 +28,13 @@ export function newSpecErr(err) {
   }
 }
 
+export function newSpecErrBatch(errArray) {
+  return {
+      type: NEW_SPEC_ERR_BATCH,
+      payload: errArray
+  }
+}
+
 export function newAuthErr(err) {
   return {
     type: NEW_AUTH_ERR,
diff --git a/src/core/plugins/err/reducers.js b/src/core/plugins/err/reducers.js
index 6b0c5d2e..795f5dd5 100644
--- a/src/core/plugins/err/reducers.js
+++ b/src/core/plugins/err/reducers.js
@@ -2,6 +2,7 @@ import {
   NEW_THROWN_ERR,
   NEW_THROWN_ERR_BATCH,
   NEW_SPEC_ERR,
+  NEW_SPEC_ERR_BATCH,
   NEW_AUTH_ERR,
   CLEAR
 } from "./actions"
@@ -45,6 +46,15 @@ export default function(system) {
         .update("errors", errors => transformErrors(errors, system.getSystem()))
     },
 
+    [NEW_SPEC_ERR_BATCH]: (state, { payload }) => {
+      payload = payload.map(err => {
+        return fromJS(Object.assign(DEFAULT_ERROR_STRUCTURE, err, { type: "spec" }))
+      })
+      return state
+      .update("errors", errors => (errors || List()).concat( fromJS( payload )) )
+      .update("errors", errors => transformErrors(errors, system.getSystem()))
+    },
+
     [NEW_AUTH_ERR]: (state, { payload }) => {
       let error = fromJS(Object.assign({}, payload))
 
diff --git a/src/core/utils.js b/src/core/utils.js
index 4595c798..8babdbd8 100644
--- a/src/core/utils.js
+++ b/src/core/utils.js
@@ -494,8 +494,8 @@ export const validateParam = (param, isXml, isOAS3 = false) => {
     let listCheck = type === "array" && Im.List.isList(value) && value.count()
     let fileCheck = type === "file" && value instanceof win.File
     let booleanCheck = type === "boolean" && (value || value === false)
-    let numberCheck = type === "number" && value
-    let integerCheck = type === "integer" && value
+    let numberCheck = type === "number" && (value || value === 0)
+    let integerCheck = type === "integer" && (value || value === 0)
 
     if ( required && !(stringCheck || arrayCheck || listCheck || fileCheck || booleanCheck || numberCheck || integerCheck) ) {
       errors.push("Required field is not provided")
diff --git a/src/style/_models.scss b/src/style/_models.scss
index 23b349d6..feb46a87 100644
--- a/src/style/_models.scss
+++ b/src/style/_models.scss
@@ -3,14 +3,16 @@
     font-size: 12px;
     font-weight: 300;
 
+    @include text_code();
+
     .deprecated
     {
-      span, td {
-        color: $model-deprecated-font-color !important;
-      }
+        span,
+        td
+        {
+            color: $model-deprecated-font-color !important;
+        }
     }
-
-    @include text_code();
     &-toggle
     {
         font-size: 10px;
@@ -87,7 +89,8 @@
         background: rgba($model-hint-background-color,.7);
     }
 
-    p {
+    p
+    {
         margin: 0 0 1em 0;
     }
 }
@@ -106,6 +109,7 @@ section.models
         h4
         {
             margin: 0 0 5px 0;
+
             border-bottom: 1px solid rgba($section-models-isopen-h4-border-bottom-color, .3);
         }
     }
@@ -114,6 +118,7 @@ section.models
         font-size: 16px;
 
         display: flex;
+        align-items: center;
 
         margin: 0;
         padding: 10px 20px 10px 10px;
@@ -122,7 +127,6 @@ section.models
         transition: all .2s;
 
         @include text_headline($section-models-h4-font-color);
-        align-items: center;
 
         svg
         {
@@ -202,7 +206,7 @@ section.models
 
     &.deprecated
     {
-      opacity: .5;
+        opacity: .5;
     }
 }
 
@@ -218,14 +222,16 @@ section.models
 {
     font-size: 16px;
     font-weight: 600;
+
     margin-right: 1em;
+
     @include text_headline($_color-delete);
 }
 
 
 span
 {
-    > span.model
+     > span.model
     {
         .brace-close
         {
@@ -237,8 +243,8 @@ span
 .prop-name
 {
     display: inline-block;
+
     margin-right: 1em;
-    width: 8em;
 }
 
 .prop-type
diff --git a/test/core/utils.js b/test/core/utils.js
index 918d8431..73861845 100644
--- a/test/core/utils.js
+++ b/test/core/utils.js
@@ -700,6 +700,14 @@ describe("utils", function() {
       }
       assertValidateParam(param, ["Required field is not provided"])
 
+      // valid integer, but 0 is falsy in JS
+      param = {
+        required: true,
+        type: "integer",
+        value: 0
+      }
+      assertValidateParam(param, [])
+
       // valid integer
       param = {
         required: true,