Never mind on the soft limit LED question, I found my 'issues' causing it on two different machines for two different reasons. This was after seeing it work properly on a third machine which is a simple 3 axis setup w/ UC100.
problem Machine 1) Running slaved X/A axis on gantry. the fact that A axis does not report position on the DRO, but respects the soft limit values set on X was the problem. I had to open my soft limit range on the negative side on X axis by a few thousandths to get LED to clear because of the A axis. It seems like the slaved axis should be excluded from triggering the soft limit, given its DROs give no feedback.
problem Machine 2) The soft limit LED was triggered by a rotary axis, I wound up putting a huge soft limit span to allow several rotations either direction.
I still see the soft limit 'always on' in demo mode in the office though, which I assume may just be a nuance of demo mode... But really it was my office computer that sparked the original question
regards
Eric