Null pointer exception while trying to precompile

Unfortunately, nullpointers can mean a number of things when working with the precompiler (or other tools that use the rom/prom apis).

I would start by verifying that you have the correct repository path in your .server file. Start by using an absolute repository path, for example, instead of a relative path. An error in the project path (in the server file) will also generate a nullpointer. 

It can also be caused by classpath issues, but I would start by checking out the paths - they are easier to diagnose :-) 

Regards, 

Jostein