1.)Make a backup of the old cmstartup.bat

2.)If you have customized Visio templates and stencils saved under the cm installation folders backup those files as well.

3.)Go to the OS control center/ uninstall programs
Uninstall ConnectMaster and
Uninstall MapX 7.0 or lower (if not used with other SW), do not uninstall after installation of CM6.75

4.)Manually delete the entries of CM in the start menu and the CM installation folder, e.g. cm600, do not delete cm nor oracle folder