thanks to your post I tried out more things
the first thing that your "position calculation" make me think about was : screen resolution
of course my tv being old and such the profile for unique display on tv changes the resolution of display to 800x600 (although it isn't really the final number of points displayed it's not really relevant to this discussion)
so I began trying out different resolutions on both my computer and my girlfriend one's
and sure enough here are my results :
-gf computer with 1680x1050 rez : any resolution below 1680x1050 will mean losing the famous bar I talked about earlier , 1680x1050 is fine though.
-my own computer CRT with a quasi-permanent 1280x1024 rez but able to go higher (1600x1200 MAX) :
any rez below 1280x1024 will get no menu showing up
1280x1024 is just fine
1600x1200 is VERY insteresting and give out this placement
in the end I'm surprised I'm the only one who got to exhibit this problem, I suppose the program have a problem getting the resolution change and repositioning the menu accordingly