Parts of map (sublevels) not loading after engine update

Hi,

we have recently upgraded the engine from the 4.7.5 to the 4.13 version. I know it’s a big jump but it needed to be done for reasons that are unimportant now.

We have a big Persistent Level with a lot of sublevels, most of them with Streaming Method set to Blueprint. After the update some parts of the world, corresponding to whole sublevels, are missing, both when hitting play on the editor and when launching to the target platform. However, those same sublevels show correctly on the editing view.

I have tried setting all the sublevels Streaming Method to Always Loaded to see if it had to do with the streaming, but the problem persists. If I search for Actors that I know are in those sublevels in the World Outliner during play, they don’t appear there either.

Has anyone encountered a similar problem? Any tips on what could the problem be, or what can I do to get useful info or debug the problem?

Thanks!

Apparently one of the Streaming Volumes broke with the Engine update, I managed to get it to work by deleting it and creating a new one with a similar shape. However, the original one was quite complex and the new one I created wasn’t exactly the same, so maybe there is some bug with certain configuration of Streaming Volumes.