Okay, so with Imbued Fire in play, and CQC showing up in the Enviroment, how does the round resolve?
Do the Heroes choose which damage type (Fire or Melee) will be predominant for the whole round, or does each Hero pick for themselves (if so, do they choose once for their turn, or can they change their choice as it suits them)?
Thanks!
Hero choice, each hero picks individually for each instance of damage they deal. Anything that does not say "At the start of the turn" or "At the end of the turn" is hero choice. X of turn things happen in the order they entered play.
When you say CQB, do you mean CQC? Close-Quarters Combat, in Megalopolis?
And if you do, could you please spell it out in the title? It will make searches work better. 
If you indeed mean Close Quarters Combat the answer is whichever one came into play most recently.
Static effects (Effects that do not have activation text, like being on a one shot or text starting with "whenever") have no timing, they apply to the field as soon as the card they are on hits the field.
So there is no simultaneous activation, because the effects are not activated, they come into play and sort of take over the field.
I'm not so good at explaining it, but official ruling is that static effects do not have timing, so the question isn't actually a timing question.
No, as Matchstickman said, it's player choice based on the previous ruling.
Whenever you intiate an attack, it follows these steps:
1) Determine attack type, then, 2) determine all modifieres from all sources. If there are every multiple effects for each step, you can choose the order that the effects happen in. It doesn't matter which card came out first, or if something is a "static modifier" (this concept doesn't apply to SotM).
FWIW, this answered is confirmed by the Mega Computer.
We have a very old ruling that the last card that entered play takes precident (Imbued Fire vs. Close Quarters Combat on damage type change)
We have an old ruling that Static effects do not have timing.
Neither of those rulings have been superceeded. If a Static effect does not have timing then they cannot be simultaneous.
I don't know if this is intended to have changed, but nothing official so far has changed the old rulings.
Order of operations comes into play here. Order of operations states that if two effects (apart from start- or end-of-turn effects) would come into play at the same time, the players get to decide which activates first. Imbued Fire and Close Quarters Combat, both being effects that change an attack's type, most definitely come into play at the same time, and thus it is the players' choice which one activates first. I'm not sure exactly what the rule on static effects was, but since OoO was brought in to simplify things, and also so there wasn't so much keeping track of which cards in different play areas came into play first, I don't see why it wouldn't apply here.
To clarify Pydro's last point (for those who don't know), Mega Computer is a text-only prototype version of the SotM app, and the team working on it have talked to the GtG team a lot to make sure the way their game engine works is consistent with the game rules. In Mega Computer, you're able to pick whether CQC or IF activate first, which adds credence to this point of view.
Oh, and to correct myself from my own last post, it's Cramped-Quarters Combat, I believe, not Close-Quarters Combat.
Anyway, there was a ruling made last year (I remember Christopher telling us about it in person at the gaming day in London last October, so it was posted up on the forum not long after that) which stated that anything with a specified trigger piont (eg start/end of turn) will trigger in the order it was played, but anything else will trigger in the order the heroes choose. So this basically means that if both IF and CQC are out, you can choose which one takes effect "last", this overriding the other one and affecting your damage :).
This is a great and descriptive and helpful thread title, except a) the abbreviation and b) the incorrect abbreviation. It'd be better to change "CQB" to "Cramped Quarters Combat" for the sake of clarity and future searching.
I cast Summon Moderator!
The most current Order of Operations ruling actually does supersede those older rulings. Static effects were a forum created term to try and define these interactions before Christopher did away with all of that with the OoO ruling.
Any static effect without a defined timing (like damage type modifiers) are all simultaneous with eachother.
Anything that's not a start or end of turn effect are no longer bound by "whichever came out first"
I actually asked Crow to confirm it was Closed Quarters Combat, earlier, as I didn't want to change it to find out Crow intended something else. 
Awesome. I love it when my spells work, thank you.
Did you learn that one from Bullwinkle? "Watch me pull a Rabit out of my hat."
Nah, if that were the one, she would've gotten me or arenson9. "Wrong hat."
Hey there I just want to double check if we undersand the ruling
Effects such as imbued with fire and other modifiers have an order that can be determined by players. Did we play this situation properly
Wraith has Razor Ordinance and Micro Targeting computer (adds 2 damage to all projectile attacks) afterwards Ra plays Embued With Fire.
Through Order of Operations, here's what our Waraith did
Used Razor Ordinanace (base 3 projectile damage)
Applied Modifiers ofTargetting computer (Attack is now 5 given that Razor Ordianance is still projectile damage)
Applied Effects of Embued with fire (Attack is now 6 fire damage)
Was that leagle?
No, because Micro-Targeting Computer only increases Projectile damage. Once she is no longer dealing Projectile damage, she no longer gets to increase it.
I added the step you missed. Ronway ninja'ed me though
Yeah, the damage modifiers are added in this sequence:
First, determine damage type. Then, add and subtract to get the total damage. If the damage is redirected, recalculate to include any increased/decreased damage specific to the target, and exclude any of the same that applied only to the first target. So, if Ra were to hit Mr. Fixer (with pipe wrench and Driving Mantis) for 3, it would be reduced to 2. Then, he could redirect it to someone else (let's say Set) without Damage Reduction, bringing it back up to 3, and then increase it again because of the nemesis bonus.
Just to clarify the Nemsis bonus would not be applied if the target was say Anubis as opposed to The chairman right?
The bonus would be applied to Anubis, but not the chairman. Because Ra is ultimately dealing the damage, his nemises take extra damage, but fixer's don't, because he is just redirecting it
Except that "Static Effect" has been used by Admins multiple times when making rulings. Christopher's ruling on OoO handled simultaneous effects. The old ruling that Static effects don't have timing isn't superceeded by that because the whole point of static effects not having timing is that they weren't under the OoO to begin with.
We also already have an exception to the OoO ruling with Informant. While all of this is nice and clean, what it isn't is official. Because there hasn't been a direct ruling that did away with the ruling that some effects don't have timing, the application of the new OoO to static effects is questionable.
I can tell you there's no such thing as "simultaneous" or "static effect" in the SotM digital version. I still need to get that blog post about the damage dealing algorithm written up… probably in some of my copious free time 
All of those old "static effects" are now simultaneous with eachother. They are assumed to trigger at the same time. That alone puts it under the heading of the OoO. Without distinct timing clauses, you can't rightfully argue they trigger consecutivy.
The OoO was not just about Simultaneous effects either. The heart of the ruling was to do away with "what card came out first" tracking, except for the specifically mentioned Start/End of turn tracking. And It specifically said at the end of the post that any other ambiguous situations are at the discretion of players choice. So even if "static effects" are not simultaneous, they fall under "ambiguous" due to the lack of timing clause. Either way, its OoO material.