Lots and lots of posts in this section about using resin parts. Do a quick search and you'll find lots of posts.
The best way I've found to cut them loose is to use a razor saw. Resin is very soft and breaks easily so be careful.
You will need to use either cyanoacrylate (CA) glue or epoxy to glue them in place. Priming helps the paint stick much better, especially acrylics.
Resin dust IS dangerous. Use a dust mask to prevent breathing the particles and clean the dust up when you are done. Wet sanding will help hold the dust down to.