SPMMouse ongoing maintenance effort
SPMMouse does not seem to be maintained by its original author anymore. This project attempts to maintain SPMMouse sources so that they keep working with newer versions of Matlab.
SPMMouse has been written for SPM5. This version requires a recent release of it from the SPM5 ongoing maintenance project. This should not be an issue: if you have landed here, it has to be because you need to run SPMMouse under a recent version of Matlab, which in turn requires such a recent release of SPM5.