I'd really prefer that you don't overwrite the updater GUI. The updater is stable, and it needs to be.
I'll take a look at the hooks you've provided again, but last I recall, I wasn't able to actually make something functional without keeping some of the hack-ish work.
For everyone that's having problems with the updater, inserting
$BLG::MM::UseUpdaterDefault = true; in the console and restarting Blockland will bypass the Glass skin of the updater and stick to Greek's. I'll investigate the problem more when I can.
EDIT: Most of the updater code is revised from your last PR, I don't think I've changed anything since then. The Updater GUI isn't be rewritten at all, just an alternate one is being pushed.