diff --git a/src/services/challenges.js b/src/services/challenges.js
index 079a5ef7..5c453f66 100644
--- a/src/services/challenges.js
+++ b/src/services/challenges.js
@@ -19,6 +19,25 @@ export const ORDER_BY = {
   SUBMISSION_END_DATE: 'submissionEndDate',
 };
 
+export function fixColorStyle(registrant) {
+  /* eslint-disable no-param-reassign */
+  // set default color
+  registrant.colorStyle = 'color: #555555'; // grey
+  if (registrant.rating) {
+    if (registrant.rating >= 2200) {
+      registrant.colorStyle = 'color: #EA1900'; // red
+    } else if (registrant.rating >= 1500 && registrant.rating <= 2199) {
+      registrant.colorStyle = 'color: #F2C900'; // yellow
+    } else if (registrant.rating >= 1200 && registrant.rating <= 1499) {
+      registrant.colorStyle = 'color: #4C50D9'; // blue
+    } else if (registrant.rating >= 900 && registrant.rating <= 1199) {
+      registrant.colorStyle = 'color: #258205'; // green
+    }
+  }
+  /* eslint-disable no-param-reassign */
+  return registrant;
+}
+
 /**
  * Normalizes a regular challenge object received from the backend.
  * NOTE: This function is copied from the existing code in the challenge listing
@@ -340,15 +359,11 @@ class ChallengesService {
 
     if (challenge) {
       registrants = await this.getChallengeRegistrants(challenge.id);
-
-      // This TEMP fix to colorStyle, this will be fixed with issue #4530
-      registrants = _.map(registrants, r => ({
-        ...r, colorStyle: 'color: #151516',
-      }));
+      registrants = _.map(registrants, registrant => fixColorStyle(registrant));
 
       /* Prepare data to logged user */
       if (memberId) {
-        isRegistered = _.some(registrants, r => r.memberId === memberId);
+        isRegistered = _.some(registrants, r => `${r.memberId}` === `${memberId}`);
 
         const subParams = {
           challengeId,
@@ -366,7 +381,7 @@ class ChallengesService {
 
           // Add submission date to registrants
           registrants.forEach((r, i) => {
-            const submission = submissions.find(s => s.memberId === Number(r.memberId));
+            const submission = submissions.find(s => `${s.memberId}` === `${r.memberId}`);
             if (submission) {
               registrants[i].submissionDate = submission.created;
             }
diff --git a/src/services/submissions.js b/src/services/submissions.js
index 12f27021..ffdd1701 100644
--- a/src/services/submissions.js
+++ b/src/services/submissions.js
@@ -60,8 +60,16 @@ class SubmissionsService {
 
     const url = `/submissions?${qs.stringify(query, { encode: false })}`;
     return this.private.apiV5.get(url)
-      .then(checkErrorV5)
-      .then(res => res.result);
+      .then(res => (res.ok ? res.json() : new Error(res.statusText)))
+      .then((res) => {
+        const unique = [];
+        res.forEach((x) => {
+          if (unique.filter(a => a.updatedBy === x.updatedBy).length < 0) {
+            unique.push(x);
+          }
+        });
+        return unique;
+      });
   }
 
   /**