If you are having an issue with going through portals where the game is either locking up or going to a black screen, please make sure that you have not unchecked the following two options: 

“Show notification for screenshots” 

“Allow automatic screenshots”

As of right now (November 19, 2018), these both need to be checked. Unchecking them can cause the game at portal points and some other points in the game to lock up or go to a black screen. The developers are looking into a fix for this issue, but for now please keep these two options checked.