To add TMTab to your Protégé installation you must:
"Project" menu, select
""Configure..."". In the dialog that
appears, check the entry labelled "TMTab".
Once you have restarted Protégé, if you do not see the TMTab entry in the configure dialog, the most likely cause is that tmtab.jar is not in the plugins subdirectory of your Protégé installation - if necessary, copy the file from the temporary directory into the plugins directory by hand and then restart Protégé.