Ok dont know if anyone care but here some info ive gathered


+x is to the right
+y is DOWN

The catapult is placed relative to the first birds starting position
Thus if you give your first bird a -ve y co-ord its in the air and the catapult will be higher up.

changing bird order is easy as it just changing there start_number
I have also managed to swap a pig and a small square ligth block on level 12
by swaping there y co-ords as there x was more or less the same


i havnt made head wau with things like density yet, but im trying