Hi, thank you for your constructive feedback. The run button works mid-air to allow more precise platforming. I wonder where are these 2 sections you're talking about, but there are some hidden mechanics that could have helped you reach these areas (smashing the attack button while performing the dash attack gives you more speed, however, you should be able to reach every platform in the first level without that mechanic).
Button reconfig is something I consider in the future, but it's a bit complicated and overall long to set up and will be implemented later.
I'll try to improve lots of things in the next update coming this month!