Agreed, movement was a bit of hurdle to understand. I would prefer WSAD + space for regular movement and maybe LMB + RMB for record/rewind? Or something else on the right hand to record/rewind.
I also had a really hard time understanding how recording and rewinding might help me get through this first gap. I tried recreating the short video, but I couldn't make any way. It seems like there would be a second jump mid-air, but it doesn't happen for me. I am clueless, but maybe that's just my platformer skills :)
Nonetheless, cool concept and I would love to see it polished! I loved the visuals too!