if you can't make ox and oy work then there is something fundamentally wrong with your engine. We did it in ARC after all, wasn't even all that difficult.
as for rewriting the scripts to achieve what ox and oy do, if your working on the engine level then you should be able to do it yourself. all you have to do is draw the window contents to a separate bitmap and then blit a small portion (the portion determined by the ox, oy position; and the content space width, height) of that bitmap into the window content area.