I think i found why the Sonic Blaster(birdscarer in wad files) do crash the game sometime . I dont found this information before on RRU.
I realised it's offen when some monsters are next the object (lava/ice/rock) and when i'm going in they game folder we can found "runpanic.lws" but when open"Lavamonster.ae" we cant see a line about this animation. it's the same for the three monster.
After that i go in "lego.cfg" and change for all monster the line
Scare