I have a Linux simulator ready, though it isn't in the update script yet. I also have a Windows copy of the simulator compiled, but I haven't tested it yet, although it should be ready in the next few hours. If there's any problems with it, feel free to let me know. I do know that the estimated runtime setting will cause it to crash, because I had to add a few if statements so that it will compile. I'll try to fix that sometime soon.

Links:
Linux: http://chrisjs.com/rockbox-sim-linux.zip
Windows: Not released yet