Before you can use Goomba, you need to add some GB roms to the emulator.
You can do this with various tools (Goomba Front etc.).
Or you can do it manual by using a "DOS" shell:
copy /b goomba.gba+game1.gb+game2.gb goombamenu.gba
you can also insert a splashscreen between goomba and the first game if you want to.
Make sure the game's size are correct and that they contain a "real" Nintendo header,
some unlicensed games seem to use their own headers.
Menu navigation: Press L+R to open the menu, A to choose, B (or L+R again)
Speed modes: L+START switches between throttled/unthrottled/slomo mode.
Quick load: R+START loads the last savestate of the current rom.
Quick save: R+SELECT saves to the last savestate of the current rom (or makes
a new one if none exist).
Sleep: START+SELECT wakes up from sleep mode (activated from menu or 5
minutes of inactivity)
Link transfer: Support as the multiplayer link isn't implemented yet. Maybe I can do normal GB to GB link also I don't know yet.
PoGoomba: If you wish to use Goomba with Pogoshell
just rename goomba.gba to gb.bin