It's still not really clear to me what this script/tool is supposed to do.

It's already relatively simple to setup FTL formations using Keyclone with a single key to spread and a single key to follow regardless of which WoW window has focus. This involves the single key on master translating to a single real-time single key press on slaves principle which I personally think is important to follow.

Granted, if you want to have a single spread key, you are limited to simple formations such as a cross, instead of a line. For me a cross works very well for basically everything and has the advantage of being the most efficient way to maximize inter-slave distance for AoE type effects not to stack.

I have my keymaps such that my spread button always sets up a cross with the active toon character in the middle. The active toon then runs forward to engage if needed.

Briefly, I have some additional keys bound to movement. I use WASD with keyclone set not to pass and arrow keys ,which do pass, to move all 5 toons. My third binding set is "[" forward, "]" back, "{" strafe left, "}" strafe right on all toons. In Keyclone, I have keymaps set up so that the ` key (my spread key) sends a forward, back, left, and strafe to each of the non-dominant toons. For instance:

Toon A map:
`-> SpreadA
[ -> SpreadB
] -> SpreadC
{ -> SpreadD
} -> SpreadE

Toon B map:

} -> SpreadA
`-> SpreadB
[ -> SpreadC
] -> SpreadD
{ -> SpreadE

Toon C map:

{ -> SpreadA
} -> SpreadB
`-> SpreadC
[ -> SpreadD
] -> SpreadE

... and so on ...

I manage my DPS with focus, just use FTL for formations.

While smexier formations are certainly doable, I don't really see the point. Is there some problem you're actually trying to solve here?