Walter - all screen shots from the Lowrance are long gone unless you can still access the original ifly forums! ..but basically it gave an OBS function. You could actually use OBS with any waypoint whether VOR or otherwise. There was a rocker button you held right or left to dial the OBS.
There really isnt another way with a GPS to fly from a waypoint with a gps - legs always take you to.
with the OBS function I could dial in a radial to or from any waypoint and essentially the HSI and CDI pages worked just like a VOR, even better that's where the NMEA data for the autopilot would track. no reception issues and no accuracy loss further out from the station as the gps signals dont fan out.
Putting aside holding, procedure turns and missed approaches. Maybe I just want to track outbound from somewhere on a given heading looking at stuff, I'm not actually navigating to a specific predefined waypoint.
anyway it worked as an OBS function/mode. If I recall correctly when I picked a waypoint "station" and set an OBS it would track that to oblivion which was fine.
When I was done with the OBS and switched back to regular mode I'd resume my flight plan if I had one active.
I won't argue I'm sure I'd use it less often than I used to but that's how it worked.