OK,

I tried using the above Primo version with Here maps, it installed but wouldn't open (missing zipped file)
I went back to the TomTom maps and had the flashing screen again.
I had the bright idea to turn off wifi on my radio, and the flashing stopped! I FIGURED IT OUT! (lol)
Then after a couple miles it froze; map showing but not moving.
I restarted iGO a mile later and it worked flawlessly for the rest of my drive.
Got in this afternoon and booted it up to drive home; flashing again. Then froze to black screen.
Multiple restarts had same effect, the fourth or fifth time it was working flawlessly again.

Now I'm thinking it's my android radio, maybe iGO is demanding too much from the RAM or is competing with something else for memory. I need to get some sort of utility or reg cleaner or something and check out that aspect. I am running it from the SD card and did not install it internally, that might be an issue, too.