Got 31, but I think you can only get that by cheating...since I assumed paintings were blocks, I accidentally hit the 'last' painting where I could see light coming though forgetting that one hit would knock it down and it revealed the door. Which I assume you can't open unless you knock the painting down, which is breaking the rules of destroying blocks.
However, if you are following the idea that paintings aren't blocks (which some consider more appropriate), then neither are levers, buttons, and ladders, making the map much easier.
Very nice map, I enjoyed it.
First run through I got 20g, but that was taking the water jumping way and not destroying pictures. then I got bored and checked behind the ones at the end, then dug through a wall to inspect circuits, got back to the start and did it all again this time taking the lava way and checking behind pictures. Ended up with 30 that time