I think the problem is, it's a minimum of three turns (grab books in summoning library, study books at summoning library desk, cast summon in/near summoning library) before anybody can do anything to any other player that's not fluff. And at one update per week, that's most of a month gone by.
For a structured, rule-based system like this, you need a much more frequent update schedule - once a day would be preferable, if you didn't just move to running it over a chat protocol and putting out "updates" every few minutes. Each turn has a limited set of actions, which means people don't need to think as much about what they'd like their character to do, and can easily plot out what future turns will look like.
A freeform system, like MGI, can work with a slower update schedule, because a given update can cover anything from a few seconds to a big chunk of a day, depending on what the players and the DM are up to.
So... if you want my two cents' worth... declare - NOW - that you're moving to a much more frequent update schedule, and the next update will be coming one time period from now. If anybody doesn't post, then they don't move for the turn. Cut down on the description, or pre-write it - you've got one character who's triggered anything more complicated than "you retrieve three books", and that was merely a generic description of an NPC which you can copy for anyone else who spots that NPC.
I get the feeling that you were trying to create a system of about the same complexity as
ODiC, maybe a little more... if you don't mind me tooting my own horn, you could look at some of the threads there for clues as to how to update more easily, e.g. everyone got the same start-text, the same first-encounter text, fairly similar second-encounter text, etc. etc.