Here's our situation:  We came up with a great premise and set of characters and issues... then the Producer had to bow out.  Can't run the series.

We hate to just drop it, but none of us is enthused at the idea of dropping our characters in order to Produce, either.

So does anyone have any ideas of how to pull this off at all?

Best Advice I could come up with here, is that you need a ignition point. The first conflict to set things off, and then go from there. Since everyone is supposed to take turns, then you're good to go once you've got the ignition point.

Here's my suggestion. Do some group creation at the start of the session. Talk it over amongst yourselves, ideas for where the campaign should be heading, or might go, and come up with a ignition point each session. Then simply take turns as normal. If everyone does a pass, and nobody wants to come up with something, then it's time for another group head think, to get yourselves going again.

Nobody's a producer, and you are gaming by committee... but at least it's what everone agrees on. You could also adapt the mechanics from Univeralis. Bid on the next scene, or bid to the series adding elements to the story until you've wound the spring enough that folks can start saying "Hey! I just got a great idea for a scene!"

Someone has to do the Producer's job for PTA to work. You could try rotating Producer-ship, so when your protagonist has a 1 Screen Presence, you produce the episode and your character is an NPC, basically.