As title really. Having the ability to save in 'Endless' mode would be a great feature.

I like to try and improve layout when they fail in main game so often use 'Endless' once that happens. It just seems a shame that to start another map you have to give up on your last one. Sometimes I don't feel I've finished with an 'Endless' map, but have to give it up so I can do another main game map.