Re: Third Age Issue
A return to menu will leave a message in the error log, most of the times it's an error in the descr_strat file. If memory serves right the log will be in the logs sub folder of the main game (medieval II total war\logs).
Open with Notepad and scroll to the bottom, that's where the message will be. Or compress and upload the log for someone to have a look.
A simple way for Steam to start the mod: open the BAT file in the Third Age folder (right click, choose 'edit') and replace kingdoms.exe with medieval2.exe
Save and use your TATW desktop short cut as usual.