I am very sorry, but I thought the fog distance was fixed in the September fix.
However, after loading my map and working on it for several hours and saving it several times, there is still an annoying problem with the fog distance in TAB-TAB.
Anyone having the same problem?

Seems fine here. I notice your settings are extremely high, I think that is the only issue here. Look at my settings, way lower and presto fog if you set such a high maximum and minimum distance you will see no fog. Just try lowering them to more useful numbers and you should be fine. As is, your settings are probably off the map entirely

Your fog value exceeding the slider max by default is a result of the previous bug that was supposedly fixed.

The only way to fix this is to set Fog Nearest to 1 and then click on the Fog Distance slider until you bring it to 50 or so. Then save your map and close Game Guru. When you re-open it it should start to remember your settings and ignore the 1500 default from the bug.

Clicking on the Fog Distance slider, will require many many clicks. It can be a bit tedious and even physically painful but once you get it to the middle and save, you should be good.

Thank you for your answers, DVader and Teabone !
The method suggested by Teabone helped me get the fog distance on my map back to normal.

Glad you got it working. Knew there was something up with such crazy numbers on fog distance!