Hi, I am the author of guile-sdl2, Chickadee, and Sly! Chickadee is probably the best thing out there for Guile right now, missing features and all. It is built on top of guile-sdl2 and guile-opengl. A simple 2D game should be feasible with it. There is some documentation but it's not great. If you do end up using Chickadee, you can post questions in this thread and I will try to reply.
I don't recommend using Sly. It was an interesting experiment that I started back in 2013 and I used it to make my "lisparuga" game entry a couple years ago, but it's an experiment that didn't work out very well. Thus it has been abandoned.
Hope this helps!