What the title says, imagine I'm going from 100 to 150 BPM increasing by 5 and I fck up at 135 and want to restart again so I can practice slowly, I click the "timer" with the BPMs to stop it, then press start again and goes back to 135, there should be to start from 0, that is your decision but I would make default to go back to the start if it is stopped by pressing the "timer" and then another button down with the pause ( || ) icon and then when it pauses and you press start continues with the BPM it was on.
Hope I explained myself,

primarily for the offline functionality

get rid of jqueryKonb and jquery. create the knob canvas on own.

code for reference: https://www.html5rocks.com/en/tutorials/webaudio/intro/js/rhythm-sample.js
sounds: https://github.com/cwilso/web-audio-samples/tree/master/samples/audio/sounds/drum-samples

so it goes down after hitting the max tempo

I love this.

Thought I'd give you a feature request because why not. Do with it whatever you want :-)

While I'm practicing I would love to be able to hit a single button that simply drops the tempo back down 5 bpm or whatever and resumes increasing as before. An "ack I'm just in a little over my head, give me some breathing room" button. I've never seen anything that had that but I would use it a lot,

has some new features which we could use and mostly because it gets rid of jquery.