The Cloth Map Only option is bugged in that the game sometimes reverts back to showing the terrain when leaving the options screen.
To Reproduce:
1) Zoom out to Cloth Map
2) Hit ESC and check the "Cloth Map Only" checkbox under the "Gameplay" Tab
3) Click "Back to Game" button
4) Notice that game stays in cloth map when zooming in - fine up until now
5) Hit ESC again
6) Click "Back to Game" button again
7) Notice that game is stuck now in terrain only pseudo mode - ie bugged
8) Hit ESC for a third time
9) Uncheck "Cloth Map Only" checkbox
10) Click "Back to Game" button for third time
11) Zoom in until cities and units visible and then zoom back out to Cloth Map
Now we are back at step 1) again. Repeat Ad Nauseum.