You probably don't even need to run the cleanup tool, just clear your temp folder and delete comodo folders from the programdata and program files directory, as long as you don't have other comodo products installed e.g. comodo dragon, secure shopping, etc. Then run the CIS installer by using run as administrator context menu instead of just double clicking it. If it still fails to install you can grap the installation logs from the temp folder, look for cmdinstall.7z archive files.