[Rwp] Action loop: how to work?

[germano carella]

Hi to all,
I seen in actions: set action loop, goto end of loop and goto start of loop.
Ok, but how can I use it?
If I starta loop, i must run some actions. Then, when I verified some 
conditions I can end the loop.
Now, in reaper, How can I verify these conditions?
Maybe in a script file, I can check state of a variable, before ending 
the loop, but, in a custom action I don't know how to end a loop.
Some suggestions?
Thanks!