We got the logs by e-mail, unfortunately I could not find the mail with the aip file and executable, probably they were blocked because of the attached exe file.
Looking at the uninstall log I see the info code 1321, which means "The specified user account is not a member of the specified group account.", when the installer tries to uninstall the file "C:\Program Files (x86)\PicturePaste.com\PicturePaste 2\PicturePaste.exe", so it skips it. Have you applied any special permissions on the install folder?
Also, when you run the EXE I assume you are elevated from the beginning of the uninstall, does the elevation prompt appear when you launch the uninstall from Control Panel? Do you have UAC disabled on the machines?