Hello Guys,
I didnt find anything so I post here my current problem. Since my passage from 4.19 -> 4.20 I can’t make my changelevel system work.
It’s really simple I use
GetWorld()->PrepareMapChange(LevelsToLoad);
With LevelsToLoad being an array of FName linking to the level in their right folders. Well it was working in 4.19 so shouldnt have changed.
Then once my levels are loaded I call the CommitMapChange() and here comes the drama.
Instead of loading me my level and all the sublevels it contains (which are explicitly inside the leveltoload array), it loads my just a black screen (I think it’s the persistent which is empty).
When I debug in standalone mode, when calling the map change, the code stops at this line in world.cpp : (line 2921)
if (ensure(StreamingLevelToAdd->GetCurrentState() == ULevelStreaming::ECurrentState::Removed))
With StreamingLevelToAdd being the first level not being the persistent one.
Can’t seem to figure this out and its driving me nut. Please send help 
<3