I tried thoroughly to make sure there were no extraneous solutions to this one, but if someone finds one, let me know! Also, the verification of the groups was near impossible to make fair, since the keyword is just one letter, so employ the honor system there :P

fun! But hard, because there were lots of ghost solutions to reject.

I like this one. Well done.

Great grid. Fun and enough of a challenge

Great fun - so many red herrings :)

really good with lots of red herrings

Really good concept, nicely done.