Let's say we have 4 groups of monsters fighting some PCs. One monster fight conservatively, and on his green die he gets a delay symbol. What happens?

Does the GM lower one of the initiative tokens by a space? If so, which one? I'd say whichever the GM wants.

Or does the GM put two recharge tokens on an action? Again, which one?

Or you could let the players decide.

I would move down whatever marker was currently acting.

I think if acting player or monster rolls a delay symbol I will not allow him to go first.

By definition: "If at least one hourglass symbol appears in the results pool, the action causes a delay. During
encounter mode, after the action is resolved, the GM has the option to either place two recharge counters
on one of the rolling character’s action cards, or move the topmost token for the delayed character on the
initiative track down one space in initiative order. During story mode, the GM may determine the action
takes longer to resolve than expected."

If the character in question is under the control of the GM (monster/NPC), the GM may either move the topmost monster token on the initiative track down or place two recharge tokens on any action the monster can use (including, but not limited to, the action which triggered the delay). The GM decides which of these two options to take, but note that if the option to move an initiative token is taken, it's not his choice as to which one to move.

You got that right mac40k

Like you I prefer to actualy answer an rule question with the right answer. that is what is written in the rulebook and given a fair interpredation of said rule. And not just say something nonsense that just poped into my head and felt right at the momement. Or worse answer with a houserule.

hint hint dear fellow forumites. Know what you talk about.

It's funny because when I look up a rules quote to answer a forum question, I'm not using the search functionality of the pdf or even the living index for that matter. If someone has a question about Talents (for example), I look at the Table of Contents, find Talents, and read until I find the quote needed. For all the crap FFG takes about the poor organization of the rules, I never have a problem finding a quote fairly quickly. I don't want to point fingers, but I feel a lot of people that post questions aren't trying hard enough to find the answers themselves.

Well you never know, maybe we're totally lazy or even stupid. In any case, the rule for delay is right there on the back cover. And I didn't even have to consult the table of contents/index/FAQ/searchable pdf. So it's not that I couldn't (or didn't bother hard enough to) find it, it's that I mistakenly thought the rule applied to player characters only, and it doesn't.

Thanks for the clarification and the positive atmosphere.

@Dhobbry - I actually wasn't even thinking of you or your original post when I responded to Mal, rather it was a couple of other posts I had responded to recently. I did not mean to offend.