hi Joe,
I think your UV exposure time of 1 to 2 mins is too short.
Depending on the the type of photoresist lacquer, it could take 5 to 10 minutes.
If you can, cut some 1 inch squares of lacquered pcb, say about 4 pieces, half cover the surface of the pcb. Piece of tape would do.
Expose each piece for a longer period, starting at 2mins in 2 minute intervals.
This will give you an idea of the correct exposure time.
Then do the same timings with these pieces in the developer solution.
You dont need to work in a dark room, just keep the boards covered before you expose them.