the error:
InitializeUI is not defined
is always a problem with the Dreamweaver Cache file and can be fixed by deleting the cache file as discussed in the Common Installation Issues PDF:
common_installation_issues.pdf
there is no need to disable the extension, then re-enable them, you just need to delete the cache file.
I have seen some stubborn cases where the cache file would not delete correctly unless you restarted the computer and deleted the cache file again.