Depending on serialization order is not a good idea here, so now it's no longer stored as a parent in the main level script but explicitly checked for when looking for a variable.
This involves passing the level explicitly to many functions. What was done here may seem a bit excessive but at least it covers everything.
Most importantly, the global ActiveThinker pointer has been moved into FLevelLocals and is now getting tracked properly by the level without using dangerous assumptions about how the game organizes its data.
