Needed to check the page to see how to play, but otherwise very cool!
I particularly liked that you utilised the rewind mechanic for multiple things: games are always better when one action has multiple uses, I found it cool you used it as the attack as well as for repositioning the cube.
I finally got to the end, but I found the last bit quite hard, having to get the timing of making a new paused box mid-air was quite hard, I ended up making a ladder of sorts by jumping on a paused cube, jumping, pressing R, spawning a new cube, pausing it and jumping on it. I'm not sure if that's how it was meant to be done, but I found that quite hard tbh haha. Perhaps being able to throw multiple cubes (you could pick up additional cubes along the way which let you throw 2, then 3 cubes at a time for example) and having them all controlled by the same rewind/pause/remove button would make for some interesting puzzle platforming.
Well done! :)