it creates a new copy when I open the high size file
Do you mean when you open it in UEFN ?
@Kalitral1 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: https://create.fortnite.com/news/using-the-creative-and-uefn-bug-reporting-form