Thanks for taking the time to play and for the feedback!
A tutorial is in the works so I'll keep your comments in mind.
I haven't implemented a global scoreboard yet, however it should save locally. Are you clicking on Retry? Perhaps its not saving unless you exit, which is something I probably overlooked.
As for the speed up, yes, it's intentional. There's a small yellow arrow on the bottom that's supposed to indicate the minimum enemy line. Clearly I didn't make it obvious enough. Any suggestions would be nice! The artist I'm working with suggested a dashed line across the screen but I thought that would be too jarring. I was thinking maybe a flag or something to indicate the vanguard. Any thoughts?