i am trying to use the helicopter_0.2 mod on minetest 0.4.6(installer). I am using the pilztest game. Hers what the debug says 03:47:51: ERROR[main]: Error loading mod "helicopter_0.2": modname does not follow naming conventions: Only chararacters [a-z0-9_] are allowed. 03:47:51: ERROR[main]: Server...