You have two basic approaches to round-robin with IS Boxer.

You can put the toons who you want to RR into an action target group.
And then use that group as the target of whatever action, be it a wow keybind or an isboxer macro.
And check the button round-robin within target group.

That will cycle through those toons, in the order they appear in the ATG.
Also, you could easily remove one of the toons from the ATG (if you were running with a friend, in the place of that character) and export to IS Boxer... and have your round-robin correctly cycle through one fewer characters.

You can also combine Send Next Click with Round-Robin within group.
I have the option (on Alt A) to Death & Decay one toon at a time.
Press one sends the keybind for D&D to the ATG and a Send Next Click action also to the same ATG, which means the action and the mouse broadcast always sync up correctly.



Alternatively, go with the older approach.

Have one step for each character that will be using round-robin.
On step 1, character 1 receives whatever.
On step 2, character 2 receives whatever.
And so on.

You can still be sending keybindings to warcraft.
Or running an isboxer macro action on each step.

If you want to have multiple things happen on each step, this can be a good approach.
For example... I have this kind of set up on Death Grip.
Step 1 = DK A (Death Grips) and DK B (uses Outbreak to place diseases on the target).
This set up is easier for me, than to have two different ATG's with slightly different ordering of each.