It is completely inoperative and simply skips to the next rule, true for .14 and .13 . Configuration in signature.
If you have two or more rules for an application, they are read from top to bottom, just like the network rules. Double check you don’t have a contradictng rule further up.
Ewen 
OK, ran another simple example (attached). Took the “allow out” rule generated by Comodo for AdAware and changed it to an “Ask and Log”, followed by block and log for other. Behavior was “block”; the ask and log was simply ignored. This behavior has been constant since beta .12 when I started using Comodo. Not absolutely necessary, so haven’t worried about it. Now have a couple of situations where it would be handy, so would like to find a solution.
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Same here. The “ask” rules are consistently ignored. I think the only use of this feature is to temporarily disable some rules without actually deleting them.