CHM files are a lot of work and microsoft considers them as a security risk, so no. Don't have the time to deal with it.
3-state checkboxes have been around for ages. To see one in action, right-click on a folder and look at the properties. Click on the "Read-only" checkbox and you can see it goes through 3 different states. There's no need for me to explain how they work, everyone knows.
Driver icons are a specific icon per game. You can get them from the usual places. Again, they've been around for at least 20 years, and they've always been in MAMEUI.