Have you updated tdebase with the latest r14-xdg-update script? That script renames all of the user's tdevelop related config files. If you are unsure, update the script and run the script with the 'force' parameter while not logged into Trinity.
Yes I did. The error message refers to a KDevTDEAutoproject plugin, but looking to what is installed in /opt/trinity, I only see TDEDevTDEAutoproject files. KDevTDEAutoproject is also hardcoded in several source files. Most likely there is something still to be done on it.
Cheers Michele