hmm sorry to hear that, how are you closing the game? The X in the menu has warnings that it will delete the save if pressed , and pressing it does close the program maybe that's the issue? :s sorry if so, the menu could be a little clearer... if this isn't the issue please let me know. Escape at the menu will close the game normally.
Yeah, I guess I must have pressed the clear save button by mistake, though that's hard to believe. I swear I shut it down normally (pressing escape) then started it up later and the progress was gone. But I've been fiddling around trying to reproduce it and it's been working fine. False alarm I guess, sorry!
It's a great little game. I'll admit I wasn't too impressed at first, but the levels get better and better, and repeating them to go for a high score is a lot of fun. And of course the sounds are awesome, and the "game feel" stuff is spot on. Blowing away hordes of those boomerang things is so satisfying.