The thread is/ was about two separate problems:

1) The Nexus variable in the debug panel "exploded" in some levels of my game, from an average value of about 40MB up to 7-49GB. The reason for this was simple though, the max_nexus set before you start the game simply was too low in some cases (in prior versions/ years ago there used to be an error message then).

2) For debugging purposes I've written a level protocol function which among others lists the functions currently running in the level. However, in my project (and at least one other project) there is one/ two functions which yield broken names and lead to crashes.