Another annoying thing in the application is the pop up warning window that appears every time you click the "Clean section" button. There's no way to remove it so you'll have to put up with it.
You can set iSysCleaner to work on system logon and set a priority level for the process. While this is a nice feature it doesn't really serve any purpose, as the program requests to be the only one running every time you need to use it.
iSysCleaner is a solid files cleaner but its functionality is somewhat riddled by some little annoying issues.