I'm pretty sure you can ignore the MEM_BAD_POINTER. It still appears in Gothic 2 (at least to my knowledge), PB just removed the actual pop up :p
Creating a new bar is... Well. LeGo doesn't work with Gothic 1 and without LeGo it's tough to render textures on the screen. I have, however, helped someone to make very old LeGo-Scripts usable with Gothic 1, including the Views-Package (which is responsible for textures). I don't have it myself but I'll drop him a message and see if I can get them. I'm not sure how hard it will to include them in your system, it's just an ugly hack so they work with G1.
I'll try to give a brief documentation in case I find them.