Great work Arwin! This is a big step to full emulation. I think though that R is probibly ging to be quite inconvieniant as a mouse button, particularly on a Mac where you have to hold it down while using menus.
Well, what you can do is play around with different setups that prefer either typing or mouse usage. Once you are typing, then you'll really want to have START as enter and Cross as space.
Also, I don't think it would be too hard to make the L key perform so that Basilisk/Mac thinks you are holding the mouse button until you press L again.
These are just some ideas though. Once you get the basics of it going, you'll find out what works best easily enough. While I agree that the L and R buttons aren't perfect for using as mouse buttons, in a full combined keyboard / mouse emulation environment I doubt you'll find a better combination that gives you everything at once, without needing to switch between different control schemes and so on. I've tried it with a number of different environments, and it works quite well.
However, if you look into the documentation for p-sprint a little, you can see that there is room for 3 custom keyboard layout groups optimised for whatever context it is running in. That would be a good way to support alternative keyboard layouts that prefer different situations. You could for instance make a keyboard layout where shift-A gives you 1, and so on, for situations where you need both alphanumeric and numeric input, like, say, WEP keys.
I'll try to put this into SVN (I don't have a login yet) and when/if I do you can feel free to play around with the code and know your changes will stick. Until then feel free to modify the source which is linked on my post above.
Sure. I don't have much time this week, but I'll do my best to chip in ...