That does not match my experience. I did looked into it and I found no consistent model of a flat earth. Lots and lots of words and sometimes even with consistent logic at times - but build upon completely false assumptions and flawed logic and therefore worthless. (you can proof anything, if your basic assumptions are made up)
"I don't think flat-earthers have accounted for Foucalt's pendulum however. "
And some of them tried and believe they did, but only when ignoring other facts and used twisted logic.
Like some parent poster had said - it is not about proof, but way more about ideology.
Otherwise they could very easily have a real proof, by sending up a weatherballoon, or organise a boat trip to the end of the world. But since they always refuse to do so (I challenged quite some with that concept) or even really think about it - they likely suspect inside that they are wrong, but rather not confirm for real, because then they would have to abolish a lot of their other ideology like chemtrails etc.
1: There are time zones in the flat earth model. The earth is a flat disc with antarctica (or is it the north pole?) at the center, and the sun moves around it in a circle, so the places opposite the sun are in nighttime
2: Believe it or not, flat-earthers believe light only travels so far, which is why things disappear "over the horizon"
4: I don't actually understand this one, but I suspect they'd handwave and talk about the same point in (1)
5: Same as (1)
I don't think flat-earthers have accounted for Foucalt's pendulum however.