Well, I do not know about the problems you guys are having with landscape mode...
I use it exclusively for play. I revert to portrait only for cheatcodes
I use an Axim 5 PDA with the same buttons you must have.
The trick is to modify the skin (graphics and code) as it it explained in the help file.
I do not know quite frankly how I did this, but now when I press the screen itself on the "health" area, it fires and when I press the screen on the "ammo" area, it activates the map.
So now in ladscape mode I have the hardware buttons in my right hand (the PDA is lying down on its left side with the bottom pointing to the right) and fire and map in my left.
I could upload both text and graphics if I knew how too.