Here are a couple recaps from 2017 and 2018:
https://dvcnews.com/index.php/dvc-p...818-typhoon-lagoon-moonlight-magic-2017-recap
https://dvcnews.com/index.php/dvc-p...ok-inside-2018-typhoon-lagoon-moonlight-magic
8:30 - 11:30 is correct for past events, but they start letting people in by 7:30. Overall it's probably busier than one may expect from such an exclusive party, but not overwhelming. Don't expect to walk in at 8:30 and find unclaimed chairs right at the foot of the wave pool or around Crush N Gusher. There will be seats, but you'll have to wander further toward the back of the park to find them.
If you head right for Crush N Gusher or Miss Adventure Falls (both near front of park) at the start of the event, you'll quickly find lines swelling to 30+ minute waits. Circle back closer to the end when people have started to head home and it's likely to be closer to 10-15 minutes.
Snacks are all-you-can-eat and I don't recall ever seeing them run out...at least not before 11pm or so. It's quite a generous supply. They'll have the full-size Mickey bars sold in the parks plus other ice cream novelties, cookies, bags of chips plus lemonade and water. Other food is available for purchase.