"Will I be able to join the Gizmoplex later?"
TLDR: Yes, you'll be able to join the Gizmoplex later, or get individual tickets for each live event – they'll just cost a little more after the Kickstarter ends.
Taken from BACKER UPDATE #2
We don't want to keep anyone from seeing the new episodes, and I know not everyone can afford to pledge for the twelve-month "Gizmoplex Season Pass" right now. So, once the Gizmoplex launches, and we start holding live events and premieres, you WILL be able to get event tickets, extra months of access, and buy individual episodes as they become available.
We don't know how much those will cost you later, but we do know they'll cost a little more than getting a Gizmoplex Pass now for all of those events. (Also, it'll be too late for your money to help us reach our Kickstarter goals, or for us to add more episodes in Season 13.)
So, if you're going to want all of them, I hope you'll consider pledging at the EXPERIMENT 100 level (or higher) now. That way, you'll have tickets to ALL of our new episode premieres, and you'll also get to DOWNLOAD all of the new episodes to keep.