For anyone still having this issue where every time you change something in your struct you lose all your data on anything that uses that struct (especially with arrays or nested structs), I was finally able to find a workaround that worked for me!
If you get this free plugin: Refresh All Nodes it allows you to right-click on a folder and refresh all the nodes in all the blueprints within that folder.
So once you have installed that plugin and enabled it under “Edit → Plugins”, here is the workaround that worked for me:
- Hit “File → Save All” just in case.
- Make whatever changes you need to your struct, then save the struct.
- Right-click on whatever folder contains everything that uses that struct, for me I just use my “Blueprints” folder. Then hit “Refresh Blueprints”. It might take a minute depending on how large your folder is.
- Once it finishes, hit “File → Save All” again.
Now all your data should still be intact even after restarting the editor or experiencing a crash! Hope this helps!