DC has written
I tried it with LuaJIT last time and it caused a ton of trouble and broke old Lua scripts. I already invested much time at that point. I had to roll back to the old version and release a new CS2D version which took even more time.
Lesson learned: Don't change a running system. I won't try to switch the Lua stuff again too soon because it's almost certain that it will break a shit ton of stuff.
It's not worth the trouble. Maybe later.