Had the same problem hope this helps, most of our Addons were broken so we reset it to factory settings via this method then added Filmon,expat tv & various other Addons as well & they all work fine now.
Note : if you don't want to uninstall everything & just want Filmon/expat tv working then you can skip to part 2 although a fresh reinstall is recommended.
Part 1)
Restore to freshStep 1)
Goto system
Step 2)
File manager & Add source -> fusion.xbmchub.com Enter name for media source we called ours hub.
Step 3)
Press menu on remote -> Goto system -> Addons -> Install fom zip -> Click Hub
Step 4)
Click hub wizard -> click plugin.freshstart-1.0.1.zip
Step 5)
Press Menu button 3/4 times on the remote so you're back at the main XBMC menu -> click on videos -> video Addons -> click XBMC Fresh start -> click yes.
Step 6)
Allow it to do its thing and restore back to fresh XBMC, then when it says it has been completed unplug the Apple tv and load up XBMC again.
Part 2:
Installing new working Addons Step 1) Load up XBMC, scroll across to system and click file manager
Step 2) click add source type the following :
http://xfinity.xbmctalk.com/ -> then enter the name of media source we called ours xfinity.
Step 3) press menu button on the remote once and click system -> Addons -> install from zip
Step 4) you will now see 6 folders, you need to click the one called xfinity -> click talk_wizard.zip
Step 5) once that has downloaded press the menu button on the remote 4 times and click on programs in the main XBMC menu -> click talk wizard -> press yes. This will now download Filmon expat tv & load of other goodies for you to enjoy.
Step 6) once that has finished Downloading & installing reboot the apple tv to make sure the changes have taken place and you can then go to the usual place for filmon expat etc which is under Videos -> addons.
If you need anymore help feel free to post below and I'll try solve any problems you may be having.
