[GIANT BUG]

The Launcher is fine, no need to caps or reply to your own posts. Make sure that your firewall is not blocking it and run it in Administrator mode.

[HELP!!! Server Problems]

Some weird issue which i never had in all my time hosting servers. The only quick solution i could find is putting online-mode to false.
Beware that this disables the authencation check for accounts (cracked accounts may join).

[Mega Promised land lag]

Problem with Promised Land is that you enter the world high in the sky, which means you will instantly generate a ton of blocks in your FoV.
You could try to tone down view distance but Promised Land is very lag sensitive. There are tons of butterflies and such flying around.

If you are in singleplayer make sure you have world type selected to Biomes o plenty.