microsoft digital media pro keyboard related question

I have run into a strange situation since I switched keyboards for my
g4 running 10.3.9:

I have replaced an aging g3 keyboard with a new microsoft digital media
pro keyboard. I would have to say that I'm quite pleased with it, but
there is one thing about it, so far, that is pretty weird.

First of all, I installed the necessary software, followed all the
directions. I'm using the keyboard with a kensington orbit trackball.

And, here it is: I cannot get into Single User Mode anymore, and I've
been using that mode for several years now.What happens it boots up, as
if I never held down the command & c keys at startup.

And then the trackball becomes disabled. I have to boot up with a mac
osx startup cd, (holding down the c key), then I pull the usb plug out
of the mac once or twice, and here I'm assuming that the mac found a
driver on the cdrom, then everything works fine, except I'm still not
able to get in using single user mode.

Has anyone else run into this?