"how can I choose a specific position for entity2, so it still moves around entity1 and is, lets say 50 quants back and 150 quants left of entity1, if you understand?"


As I've said before, use vec_rotate:

vec_set(ent2.x,vector(-50,150,0));
vec_rotate(ent2.x,ent1.pan);
vec_add(ent2.x,ent1.x);