Excellent, thank you

Sorry for the delay;
I have committed some changes to the git repo which should increase execution speed significantly, although if you were having speed problems, then "Asteroids" mode may still suffer from slow speeds, although it should be a bit faster.
I also made sloppy-timing the default again since I was having occasional issues with the more accurate timing system; This means that if you are having speed issues, you should compile like this:
OR

OR, if you still have issues and want to report the problems to me so I can fix them:

I have also just added some code for fullscreen friendliness.
If you configure with the --enable-fullscreen option, or compile with -DFULLSCREEN, then the resulting executable will run in fullscreen mode, and should look much better than previous fullscreen executables. Note that some gameplay modes will be easier in fullscreen mode because it gives you slightly more room to fly around, network games with one person using fullscreen will put the windowed player at a disadvantage. You should also be able to achieve better asteroids scores in fullscreen mode, although, you can't cheat in asteroids mode like you could before (by enabling fullscreen and staying near the edge where the asteroids can't reach).
I also changed the colors of the targets to make them look less flat and dull. I also changed a few ship colors as well.
Remember to test out the newer and faster rendering code.

It's better but still too slow. Maybe the issue relates to hardware (Indietrash didn't report any speed issue with a 2.5GHz CPU.)