the main error: count should be bmap_width() and count2 should be bmap_height() in the while statement !!!

and some tips:

put a wait(1); after panel_one.bmap = bmap_create("my_bmap.tga");
and
put a wait(1); after panel_two.bmap = bmap_createblack(bmap_width(panel_one.bmap),bmap_height(panel_one.bmap),32);
because I'm not sure they can be locked in the same frame as creation.

and yes, my_bmap.tga must be 32b, or use bmap_to_format();