As long as you spam jump fast enough you should get 3-5 consistently.

Level 3-8 is pretty hard you just have to jump over the first set of spikes but it's pretty precise.

As long as you're starting from a fresh save it should be fine.

Although finishing out every run has helped me learn some new movement and helped me get more consistent on other levels, so it's not all bad.

I'm not sure myself but you may have to delete the steam cloud save.