Are you sure it's "crud" and not an antiquing glaze? I would try laquer thinner and a spft cloth and a toothpick......and count on repainting...if I wanted the crud off... But I think I would like the frame better with a little "character". Linda C

There are others with more experience with this than me, but I would think that you would kind of "dry" paint it. Load your brush and then dab some of it off before pouncing small amounts onto the frame. I have even used wadded up paper towels with very little amounts of paint on it, almost dry, to dab on paint. I would get one of those small bottles of craft paint at JoAnns or Hobby Lobby and experiment. If you dab some on and don't like it, you could probably wipe it off. I have also used a product called Treasure Gold by Plaid Enterprises that really worked for me and was easy. I actually just remembered this after I had typed all of the above. I used it in kind of a pewter to go over a gold mirror. I used my fingers to put it on sparingly and then wiped over it with a paper towel. It was fast and easy and only cost a few dollars. Hope I am not confusing you, and I also hope others chime in with some suggestions for you.

Linda, I am now sure these are prints, but the frames are puzzling to me. The backs are all wood, but I don't know what the black front and sides are made of. They are far from perfect, with some apparent repairs and some of the paint seems to be peeling. There are also tiny nail holes where they are attached to the back. The frame fronts are not wood, and almost sound like hollow plastic when tapped. At the same time, they do not really look or feel like plastic and some of the paint seems to be peeling. Any further ideas?

Can you post a picture to provide a bigger view of the window? In your close-up that appears to be some odd looking interior trim, like it was part of a window retrofit gone bad. If you just want to fill the gap, you can buy foam filler/backer rod (sold in various diameters) at the store, stuff the cavity with the foam backer rod, and then use paintable caulk over it to fully seal the gap. If white caulk is close to your paint color, you might not even have to paint it. You can also buy window foam sealer in cans, but I caution you about how hard it is to get off if you want to change anything, or even just to clean up your hands and tools. I would not use it for this type of job. Bruce