Turns out it was all 'cockpit errors'!
When the final project was fired up, the motor was acting strangely - not stepping or partially stepping. First thing I did was look at the signal on one of the coils to the motor. Having never seen this I was startled by the signal being created by the BED when hooked up. This threw me off...
Next I discovered my software was creating WAY too high a stepping signal frequency. When I got it down to something a bit more reasonable (160 hz) it steps just fine. Now just need to clean up the code and all should be well.
As this project moves along a bit more I'll post details on my web site (http://www.avrdev.net). I'm stepping the motor using two timers - and no 'bit-banging' and no blocking during the step cycle... stay tuned - film at 11... LOL!
=Alan R.