I've been having problems hitting things with Whirlwind. Basically, attack attempts aren't even happening. While I haven't got screenshots, I can provide an old-school illustration of the exact scenarios.
One memorable example
where P are assorted slimes in Sandworm Lair and @ is me. I targeted Whirlwind, whcih is supposed to target all enemies within 1 tile of the corridor, to the right, marked with an asterisk on an empty square above. No attack attempt was recorded in the log.
In Derth, I tried again against some Gwelgoroths, targeting differently:
where E are the Gwelgoroths in question. My targeting line directly overlapped with the first two. No attack attempt recorded in the log.
The ability moved me both times, and both times I got the "[character] becomes a whirlwind of weapons!" in the log, but that's it.