You can create a mapped key.
Give it any hotkey you want.
And have it output the correct warcraft keybinding.
For example, if you want independent slave movement keys to be:
Home (Forward), End (Backward), Insert (Turn Left), Page Up (Turn Right), Delete (Strafe Left), and Page Down (Strafe Right).
You can create the appropriate mapped keys, using those keys as the hotkey.
You then assign "Q" (Other Windows) as the output of your Delete (Strafe Left) Mapped Key.
If you decide to map (via Mapped Keys) your commonly used spells/powers to: 1, 2, 3, 4, 5, Q, W, E, R, T, A, S, D, F, G, Z, X, C, V... which are all easily reached with your left hand.
The "Q" key can output something different to Warcraft, and will not conflict with the Slave Movement key.
You could also create your Macros within IS Boxer.
Rather then having a Mapped Key output a Keybinding, and having a Warcraft macro on the Keybinding.
A macro made in IS Boxer needs a unique keybind to activate.
This is something which can be pressed in game, to activate the macro.
You don't necessarily need to push the keybind, as you can assign a hotkey to the Mapped Key, which activates the IS Boxer Warcraft Macro.
Then the macro is done in IS Boxer, but the toon has everything default if you choose to one-box the toon.
I personally do most of my Mapped Keys as:
Hotkey > Sends Keybind to Warcraft > Activates Macro in Warcraft.
But that's a preference call.
You can still have the software manage Round-Robin effects.
Step 1, sends the Keybinding to Toon A.
Step 2, sends the Keybinding to Toon B.
Etc...
And each has a simple /Cast Whatever (or straight spell, without a macro).
So you can one-box the toon fine.
And when you five-box, the straight spells are still round-robin'd.
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