The material function MF_CreativeFortniteGameplay included in UEFN does not validate properly on custom materials, however when used on the included M_FortniteBase_Parent material, everything validates correctly. Really hoping for a fix to this soon.
Thank you for your report! Can you please re-post using the “New Issue” option on the Issues and Bug Reporting forums ? Posts with this feature are connected directly into our development team so we can quickly get to them!
For more information, such as how to get the reference ID, please check out the article here: Using the Creative and UEFN Bug Reporting Form
WIll do. Thanks for the response!