Puzzles: Alternative moves

You're right, tmh13, your solution is a mate in 8 and it should be accepted as a retry.

I apologise that longer mates are not playable as solutions, but it's logistically impossible to allow all longer mates to be playable. It's impossible to tell if you are indefinitely postponing checkmate, and allowing the generation of such puzzles would take infinitely long.

Clarkey, I like the way Chess Tempo deals with this problem. It tells the user the move played is good, but there's a better move available and gives him/her another chance to find it.

We have a pretty similar approach to the issue. Considering that you've done nearly 600 puzzles, you should've seen some "this is a good move but you could do better" messages.

Hmm, it's been a while since I've done problems. Maybe this was before this was implemented? Either that or I've got a terrible memory :P

In puzzle 13405 I only saw 1... Qd2+ 2. Kg3 Rg6+ 3. Kh4 Qg5+ 4. Kh3 Rh6# but not the shorter 3... Qh6# (shame on me).
This was also rated as failed. Perhaps it is possible to classify my moves as "this is a good move but you could do better"?

It should've been. The system forces SF to consider ~50 alternative lines when creating mate in N puzzles. These solutions should've been considered as retries.