It can't be a global variable, because 'screen_size' is not known at compile time, only at runtime.

Also it seems only constants can be passed to pos_x/pos_y, so that might also be a problem, although i'm not sure about Panels defined at runtime.

Finally 'ptr_remove(* splash_panel);' shouldn't compile. as 'ptr_remove' wants a pointer and '*splash_panel' is a pointer-to-a-pointer.