TO CONVERT a PC file, you must have ResEdit. Use the Get File/Folder Info... command and change the Type to DATA and the Creator to xwng. Rename the .XWI (the actual mission file) and the .BRF (the briefing before the mission, not included with all PC missions) to DEFECT. For TOD's they should already have the proper names, but if not here are the first five TOD 1 mission names:
1. DEFECT
2. ID-RECON
3. WXRGARD1
4. WXPROT2
5. ATTACKXY
TO USE A MISSION, place these files into a newly created MISSION folder inside the X-Wing Data folder. Double-click the application. The game will start, and after you pick any pilot choose to play TOD Mission 1. Make sure that Classic Missions is off in your Preference Menu. I would suggest making a new pilot for the Mission, but it isn't necessary The new level should play in place of the original. This definately doesn't work with X-Wing 1.0.