The CLS seems to want to call five or six abilities, for most level ranges.

You can easily add or remove, the abilities that it calls.
And of course edit those, so instead of calling four straight spells, maybe you have a) Totems (with Healing Stream acting as a recast delay); and b) Cooldowns; and c) a DPS castsequence.
All three are spammed, so each advances as quickly as allowed.
And if one sticks (because of in-game macro timer mechanics... ie, spell is on cooldown), that cannot fire off on a given press but something else can.



Within IS Boxer, you could debug your steps and timing by making the step send a Party Chat message when a spell would attempt to fire off.

I'd think you would want one master/spammed mapped key, that calls the other elements.
Do Mapped Key > A > Current Window
Do Mapped Key > B > Current Window
Do Mapped Key > C > Current Window

Mapped Key A
Step 1: Apply Dot A > Target: Group (all of) Warlocks
Do not Advance for 4 seconds.
Step 2: --Nothing--
Do not Advance for 22 seconds.

This would attempt to fire off, every press for 4 seconds... and then advance to step 2, where nothing is attempted and it cannot advance (back to Step 1) for 22 seconds.
You might check, in advanced, to reset to Step 1 after 6 seconds from most recent press... meaning it will reset, if you stop spamming the master key.

The issue is going to be adjusting the Step 1 timing of the each of the mapped keys.
You won't want them to cast the same dot three times.
Before advancing to the point where they cannot do anything for xx.x seconds.
But you'll want to make sure a given spell does fire off, at least once in that window.



I thought about having Mapped Key A, call Mapped Key B.
But that likely won't work, because spells have different durations and recast delays.



I'd think, using the Warcraft macro system for your timing is likely superior.
Because there is going to be a lot more people thinking how to get things to work, for say Lazymacros or on this forum.