When this issue occurs printing out the addresses of each item in the array shows that elements 2 and 3 have the same address, so for some reason the second element's value is being overridden by the third element's value.

If you do not move the added item's index, then its value will not be overridden once PIE begins.

Versions tested (issue occurs in all versions):
4.19.2 - CL 4033788
4.20.3 - CL 4369336

Steps to Reproduce
  1. Download the attached project
  2. Drag a BP_Base object into the level and select it
  3. Add an element to the "Test Objects" array, drag that item to be element 2 (index 1), then set it to be a "Base Instanced Object"
  4. Begin PIE
  5. Select the newly created BP_Base object

Result: During PIE, element 2 is becomes an instance of a "BP Derived Instance Object", and changing its properties also changes the properties on element 3

Expected result: Element 2 remains wholly unique from any other element

Have Comments or More Details?

There's no existing public thread on this issue, so head over to Questions & Answers just mention UE-64327 in the post.

Login to Vote

Won't Fix
ComponentUE - Gameplay - Blueprint Runtime
Affects Versions4.194.20
CreatedSep 20, 2018
ResolvedAug 18, 2021
UpdatedAug 18, 2021