keymaps for certain windows only

Something for the wish list for the next version, or maybe its possible now (probably with ATG?).

Lets say I have a team of 5 and I want to do scenarios so I want to enable keymaps for 1,2,3, or 2,3,4, or 3,4,5, etc.

I've generally gone with two general steps or processes, for Mapped Keys.

One of them is Do Whatever, Target > Current Window.
This is the actual mapped key, for whatever action, without any hot key.

The other is the Spam Mapped Key.
This one calls the actual mapped keys, with the actions.
Do Mapped Key > Whatever > Target...
Target by Slot number, Character Specific, or an ATG.

If I have six actions being called by the Spam Key, each attempts to fire off when I push the hot key.
For my Pally/4x DK team, I had three different spam keys depending on their general actions:
(a) Howling Blast, Frost Strike, Plague Strike, Death Coil
(b) Obliterate, Frost Strike
(c) Death Strike, Frost Strike

If you want a toggle, for an ability (I have one for IWT and another for Death Coil)...
It gets two steps, one enables and one disables.
Usually have pop up text, as a visual reminder.
The target of the toggle action, is the individual piece (that always targets Current Window); when that is disabled, the Spam Mapped Key cannot call it.

I haven't tried enabling/disabling a Key Map for a specific set of toons.
But I would attempt the Action Target Group.
Instead of having the Key Map go on for everyone, maybe use an ATG for it.
You can add/remove toons from the ATG, via another toggle type action.
The last time I experimented with this, an ATG actually had to initially have a character in it, for it to be generated when you got into the game; at that point, you could push your toggles to add/remove the desired targets from the group, and even if the group was empty at some point, you could add back to it without issue provided it was generated (by having someone in it, when you launched).

If you run different classes or hell, even the same class, it is ideal to put all the hotkeys associated to an instance within their own keymap. Then have the general keymaps broadcast to the keymap instances available.

This way you can eliminate certain keymaps and with that, also eliminate those instances associated to those keymaps. It also allows you to do something during combat like toggle off the tank and ranged when you just want the melee dps to move.I did something like this in Cataclysm during the heroic end time runs. I bound the removal and addition of certain slots to shift and ctrl modifiers but you don't have to do that. Can also toggle a notification on a click bar letting you know which windows have activated and which are deactivated.

How do I go about round robin interrupts if they all have different keymaps?

Before IsBoxer I just used castsequences in a macro like "/castsequence junk, junk, junk, junk, interrupt" with each toon having their interrupt in a different location in the cast sequence.

Why don't you use the "pro setup"?