I have spent some time lurking there in the past. (Eventually I was convinced that some, but not all of the flat earth proponents, weren't actually proponents.) I remember reading the view that dark energy or some other unknown force was continuously accelerating the flat earth upwards. One particular counter argument was the force of gravity not being uniform at various altitudes, and the answer to this was something like, "Have you tested this yourself?"
And I just posted after realizing there was a second page.