If your question is not answered then please create a new topic in the forums, and please try and include as much information as possible.
Some examples if useful information are:
1) XMBC Version (see log file)
2) Windows OS & version (and if its x86/x64 if you know - see log file)
3) Number of mouse buttons.
4) What mouse driver you have installed (generic HID device or manufacturer specific)
5) Any other mouse configuration software installed (including manufacturers software)
6) As detailed description of the problem with any relevant apps you're using that show the issue.
Remember, the more information you can provide about the problem, the more likely it is I will be able to help quickly
Thanks,
Phil