Welcome to TFES! I'm pleased to see that we're starting to get angry noobs again. First, I encourage you to avoid making assumptions. We all know the saying about what assume does to us. Instead of saying 'You can't explain x', I suggest you instead say 'How do you explain x?'. You might be surprised at how not-insane Flat Earth Theory actually is.
Things unaccounted for in your theories such as the effects of Lorentz contraction and special relativity (Which is taken into consideration, but used and applied improperly.) lead me to believe that the UA theory is false.
I'm not sure where you're trying to go with Special Relativity. You might want to expand on that a bit, but in a different thread. Hijacking threads (which is absolutely what you're doing right now) is frowned upon.
Direct "zetetic" observations such as the Sun disappearing under the horizon - and the crazy ideas such as moon shrimp - render me to submit to the idea that believing the world is flat is an exercise in lunacy fueled by paranoia and an inability to just trust the data and facts sometimes.
Don't worry, the Moon Shramp are an inside joke. Nobody actually believes in them with the possible exception of iwanttobelieve, who appears to be mentally unstable.
The cycling of the Sun is clearly explained by FET. I suggest you read the FAQ. There will be a link to it in my signature within the next five minutes.