Ensure the IS Boxer addon is enabled for all toons.

Each slot (under character sets) needs a unique FTL modifier.
If you go with the wizard, then you get unique modifiers.

Follow, for example is F11.
Even though the hotkey for follow might be Alt + F.

What happens is you push Alt + F.
And IS Boxer sends F11 with the modifiers for your slot.
Which tells the other windows, where the follow command originated.
And thus who should be followed.

You need F11 to be unbound in warcraft.
And that includes with each of the modifier combinations from each slot in character sets.

There are three FTL Mapped Keys.
Which control all FTL functions.
They are:
- FTL Target Me
- FTL Follow Me
- FTL Assist Me

In the toolkit, you want "Use FTL Modifiers" set to "On" for these three mapped keys.
And set to Default for everything else.

If none of these fix your issue, head to the IRC for IS Boxer, on the main page of www.isboxer.com