[Resolved 0.4.1] Segfault on signal placing.

[MF-]

Green number - place a signal at this segment
Red number - remove a nearby signal

It could be, of course, the already fixed bug.
Saving and loading the game before placing the last signal makes it say "block=0" on all track pieces.

[MF-]

I had more segfault crashes in other situations, but nothing simple enough to remember and reproduce.
I hope that they are caused by the same bugs.

[kovarex]

There is one problem with signals that are put on intersections as in the 11, I'm working on the fix.