I use a Picasso IV in my Amiga Technologies A4000T here with no problems. It's in the top most slot.
Maybe not a video slot problem as the two slots are in parallel. Perhaps try cleaning the edge connector on the card, which is kind of what you did by removing it and inserting it again.
It could possibly be some weird conflict with other cards?
I know a P IV, Prelude and Ariadne 1 don't work together in an A3000D. Swapped the Ariadne 1 for a 2 and it's going sweet now.
Didn't know about the PicassoIV setup screen, I'll try it next time I reboot my system. Don't recall reading about it anywhere.
