We got Zombie Fluxx last week, and yesterday I sent several rules questions to Looney Labs customer support. I just discovered this mailing list, which is a much better place for them, so I'll repeat the questions here.
I state my own answer after each question. If you disagree, I'd be interested in the reasons.
1) Can a player win while owning both Larry the Zombie and the Sonic Tranquilizer?
Yes, since the Larry card says it isn't affected by Rule or Goal cards, but it doesn't mention Keepers. I assume that Larry, being a Zombie, is affected by all cards that refer to "Zombies", such as Zombie Repellent or Hey, Over Here!, so he should be affected by Sonic Tranquilizer.
2) Look, Over There! says "move 1 of your Zombies to any other player". It should mean "1 of your Zombie Creepers", right?
Right. It's impossible to split up a multiple-Zombie Creeper (card mutilation aside).
3) If Dead Friends is in effect and you own the Shotgun, do you have to kill any Friends in front of other players before killing your own Creepers?
I'm unsure about this one; here are the arguments either way:
Yes. The intent of Dead Friends is that all Friend cards get targeted next.
No. The card says "your" Friends, so you can ignore other players' Friends. (I tend to lean towards this one.)
4) What if the Radioactive Potato or a homemade Creeper are in the deck? Several of the cards refer to "Creepers", but obviously are thinking only about Zombies, not other Creepers, e.g. No Zombies, Zombie Victory.
If a card says "Creeper" (and not "Zombie Creeper"), treat any other Creepers just the same as the Zombies. If it seems weird, make up a reason why it works that way; if a situation is too weird to accept, make a special house rule about it.
5) If playing with the Radioactive Potato or Larry the Zombie, and the Goal changes, can a player win before RP or LtZ moves to the adjacent player?
No. The movement of RP or LtZ counts as part of the result of the Goal played, so they move first, and then players check their win conditions.
6) When Out of Ammo is played, if a player has the Can of Gasoline and the Chainsaw, can he keep them both?
No. The Chainsaw is kept, but the Gasoline is discarded.
7) Is the Sonic Tranquilizer optional?
Yes. The owner of it doesn't have to ignore his Zombies if he doesn't want to. Any card that says "can" or "may" is optional, according to the choice of its owner.