Hello, Roy. As you can see, round earthers swarm en masse towards any new arrival. I can assure you that most of what has been written in this thread thus far does not accurately represent FET. I will give a go at your questions.
1. As one would expect, skepticism is an abundant trait among those that believe in a flat earth. To answer your first question simply, I am skeptical: skeptical of the established distances, skeptical of the vailidity of RE maps, etc. This may seem irrational, but first answer this. What caused you to ask this question in the first place? Did you measure the continental distances in the southern hemisphere? Do you know without a doubt the exact distance between the eastmost and westmost points in Australia? Most likely, the answer is no. Yet you still raise this question. You raise it because you were told what those distances were. That does not necessarily make it true.
2. Many refer to the Bedford experiments, which you should be able to find without much trouble. Besides that, many endorse FET because the evidence in favor outweighs the evidence against. It's as simple as that. There are many threads that give specific evidence. If you type "unique proofs" into the search bar, I believe a good thread on the matter will pop up.
3. There are many differing opinions on the scale of the conspiracy. As a result, there are many different threads on this topic. I'm sure FEG has a couple on the first page.
4.Universal acceleration causes the illusion of "gravity". It is nearly as credible as the theory of gravity, as both are incomplete theories at this point. Essentially, UA was postulated under the assumption that the earth was planar. There is just as much known about the mechanism that causes UA as the mechanism that causes gravity in each theory.That is, very little. darknavyseal brings up stratellites. Basically, satellites within the atmoplane. Also, the LORAN towers are worth your time to read up on.
5. If you believe something to be true or just, that in itself is reason enough to endorse it.
I hope this helps.