argument 'height' for macro PUSH_CLIP() is wrong in gui_tab_panel_t::zeichnen().
4th argument of PUSH_CLIP() must be height of clipping region, not the bottom point of the region.
(Incidentally, 'xx' is correct width of the tabs region. It's right for 3rd argument of PUSH_CLIP()).
Current code of the zeichnen() doesn't draw anything below HEADER_VSIZE.
Therefore, nothing would happen by this mistake.
It's not urgent. It will not immediately change anything in view of the game.
Thanks, but fixing now is anyway good.
Thanks for checking.
I think so, it should be fixed before any trouble.