Another question for anyone using this: I am unable to get screenshots that look correct. Images come out with incorrect colors, or with items missing. I tried in desktop Stella on OSX, and the screenshotting works as expected. I tried turning off TV Mode on the 77 Stella, since it's off in the desktop one, and I thought that might cause problems... but it didn't change anything.
All of the above is when I use a cartridge. I did try using a ROM from the download on page one of this thread (Asteroids), and that at least got all of the items in the shot, but they are dark. See the last attached image for that.
What am I missing?