Hi tiggerr129, and thanks for your comments!
I'm planning to work on the PPC version over the holidays, but I'm one of the unlucky persons without electricity in the Seattle area for the past week. Before that, I was on vacation for a couple of weeks, so Sudoku has not been getting much attention lately. Once the power comes back on, I'll be back in business and I'll appreciate any testing you can do with the PPC version.
Normally, you press a softkey to use the menus in full screen mode, but I think the PPC has different keycodes for the softkeys than the Smartphone, so you'll probably have to avoid full screen mode until I release a PPC version. RE: the external keyboard, you should be able to use the WERSDFXCV keys for 1-9 without the shift key for now. Also, if you like, you can use the alternate input mode in the latest preview release to navigate using the WERSDFXCV keys so you don't have to switch between the joypad/5-way and the keyboard.
I'll have a pop-up number keypad in the upcoming PPC version, and I'll switch the pen/pencil mode toggle to the left softkey. The center button on the 5-way will display the pop-up keypad, so you can play the game using only the 5-way joypad if you like (though I think it would be fairly inefficient compared to a stylus).
-David