VESC sparked, what does that mean?

Check with @onloop or Enertion support, I’m not sure if it’s a one time replacement or not.

Thank you ! Will give it a try.

Could you tell me why this happened? So I know to make sure it doesnt happen next time. It worked perfectly fine on a 3s setup.

Can’t tell for sure what happened, but it looks to be because you’re using a version of the VESC firmware with the max ramp current step bug. See more info here

http://www.electric-skateboard.builders/t/psa-remember-to-reset-your-max-current-ramp-step-when-programming-your-vesc

The first thing you want to do is to re-flash your firmware from vesc.net.au on your new VESC to fix this bug and not worry about it.