Incomplete uninstalls usually occur when one of the following is true:
1 - Program was still loaded
2 - A ".dll" file used by the program was still loaded.
Best bet would be to reinstall the program > start program > unload program > reboot > uninstall program.
After a successful uninstall procedure, do the following:
1 - Open My Computer > Tools menu > View tab > select "Show hidden files and folders" > click "Apply".
2 - Go to "C:\Documents and Settings\USERNAME\Local Settings\Application Data\Stardock" folder, and delete the ObjectDock folder found in there.
3 - Reinstall ObjectDock > Start ObjectDock > create and save a new theme.
That should do it.
Note - I do not run dual monitors, so I do not know whether this set-up is fully supported, or if there are limitations in the free and plus versions of ObjectDock. The procedures above should not present any conflicts, as you are only rewriting files, and clearing the cache folder which stores the current theme files for use on boot. The result of clearing the cache (lower procedure) will be the loading of the default settings by ObjectDock - and in this case, removing any possible conflict with the former theme used.