Now I've discovered there's a configuration menu full of lots of useful things such as frameskip options:
I don't have a reicast logo on my screen -- I presume this is only available on the Android shell. Pressing left on my dpad or analog stick is a normal gameplay action, it makes no sense for that to be able to bring up an emulator menu.You can access it by touching the reicast logo on the top left side of the screen or pressing left on the D-pad/analog stick of your gamepad.
I can't find any docs anywhere about how Windows and Linux users can get into this menu. I've tried every key on my keyboard and checking binding configs to no avail. I'm now trying to delve into the source, so I may require a tow-rope. Does anyone know if it's even implemented for non-Android platforms?