It's easily completable within an hour, once you get familiar with the maps. I was originally going to have a save, but the game ended up not being long enough to require one, which is why I went for infinite tries. It does benefit from practice, and to some degree, mapping. With saves it would become trivially easy.
I didn't mean quicksaves, just that the game should keep cleared levels cleared from on session to the next.
I cleared the first two levels, which took me a while. I imagined there would be a third one, but it turned out to be two. I played one of them for a bit and gave up (you don't necessarily have a lot of time to play at any given time). I quit the game and re-launched it to see if it had saved my progress. I was dissapointed.
I can't imagine I'm the only one in that case.
Again, it's a real shame because I was enjoying the game.
Thanks!
If anyone is wondering, it's over there: http://www.sunteam.co.uk/grelox.html
By the way, hitting HOME on the main map crashes the game with the cheats enabled.