Hi, I’ve already posted the reply under your review, but there is a pretty good chance that the Marketplace won’t send you a notification. So I’m sharing the same here.
So the project being stuck at 39% is most likely the engine trying to recompile the shaders when opening a new project. You can find more reports about the same issue in these threads:
Reddit - Dive into anything
https://forums.unrealengine.com/community/general-discussion/1710131-unable-to-start-unreal-stuck-at-39
I’d suggest leaving it for a while to finish the loading process. After the first time, it should start just like any other time If that doesn’t take care of it, we’ll look into what else might be causing it.