You certainly keep on top of this forum - thanks!
The Garmin does have a touch screen 480 x 800 and it will rotate automatically with MM. The screen display has status icons at the top for such as battery, wifi, phone signal, GPS lock and the X for "parking" a program is at the BOTTOM right, often hidden in a sub menu behind another icon when in full screen mode - Internet Explorer is an example where hitting the single icon at bottom right pulls up a bottom menu which includes X and Back among other options. MM v5.1.3 does not have that icon - in fact the settings screen has just the top status bar. The map screen has the normal Pocket Navigator buttons at the bottom. There is no "X" but Menu - Exit does the job better anyway!
I believe that WinMob 6.5.3 has moved the OK and X from top right to bottom right and this seems to be the issue - I have a similar problem with Pocket Sudoku where pressing Help-about took me to a screen with no exit similar to MM's Settings. You say that MM v5.4.2 has a different interface - I guess that I need to try it, though the documented changes to 5.4 mention only improved compatibility with Vista and W7 and do not discuss Win Mobile compatibility. Any comment on this Jason or usmmtech?
I know the small green arrow and that has nothing to do with the problem as it does not appear on the settings screen. Some folk have complained about losing some of the icons at the bottom of the MM map sreen when in Portrait mode, notably the lock and information icons. This is because icons are larger to accommmodate finger instead of stylus and the issue is solved by rotating (automatically in my case) to Landscape when the "lost" icons appear.
Since putting my question I have discovered this thread viewtopic.php?f=26&t=651
and Athorne1974's post of July 11 2010 is relevant and confirms the repositioning of the OK button. With the HD2 the poster has installed a cooked ROM which solves the issue. He does not say whether he is using latest MM v5.4.2 software.
For settings I had hoped to be able to do a registry hack, perhaps even concoct a couple of settingsn.reg files but it does not seem that the settings are stored in the registry. Nor can I find anything in Application Data or any .ini file to edit.
So currently I am stumped! It seems that the repositioning of OK and X have made problems for developers.
Another oddity that I have discovered on my 480 x 800 screen: In landscape mode MM seems to not want to redraw the right hand end of the screen (pixels 640 to800?). If I lock to location, drag right and then unlock and relock I get the location symbol (red circle) remaining at the right of the screen with another flashing one back in the middle. I don't think that happens in Portrait mode (drag to bottom of course) but I will check that.
Thanks again - I hope that MM Support may have some comments.