Afforess
The White Wizard
I've altered NO files in doing so. I literally deleted my entire Rise of Mankind folder when it was modded up with the MegaCiv pack, dropped the base 2.9 Rise of Mankind folder, and installed 1.70 beta11 over it. I then tried installing the beta10, then tried installing the beta10 and the beta11 one after the other.
RoM2.9 loads without issue
There is no beta11, or beta 10 of 1.70. The beta's stopped at 3. What on earth are you installing?