Dave,
Well this is either an installation problem or a dependancy problem is this problem was definately fixed in the 1.01 release and hence 1.1. It's been tested on different machines.
So first and foremost create a new project Hello MicroC/OS-II and then try disabling a few options MUTEX etc. if this builds it will tell us whether this is a dependancy problem. If it does not you have an installation problem.
If it does work go back to your original project and try making changes to the MicroC options apply them, rebuild and then look at your system.h file. Have the "" gone away?