I put the spammed - master click macro, onto one of the FTL DPS keys.
IE, 1 through =, with a default configuration.

The keys which the master/spammed macro calls, I place on non-FTL action buttons.

If you take a look at the mapped key, we have.
1) Do >> FTL Assist Me >> Current Window.
2) Send "key" to all windows.
So the default behavior is, slaves assist the master window, then cast their spell on whatever key.

If you want specific targeting (Chaos Rift, Snake Wrap, Web Wrap, Charming Totem, etc), include that in the master click macro.
The new order will be....
1) Slaves assist the master.
2) Slaves and master change to the new target should that target exist.
3) The spam macro calls other macros at whatever target.