I'm trying to build your citra repo from the latest commit as of writing, and video_core fails to build with "error C2228: left of '.Value' must have class/struct/union" at line 206 of src\video_core\shader\shader.cpp. I've been able to compile the official repo just fine, but your repo fails for me every time.
But Nintendo's GBA video format is different, being that it uses a custom ROM and chipset for rendering, for like the Shrek and Shark Tale titles. Been undumpable for years and years.