Good to hear that you got the project working. Troubleshooting can be frustrating, but it's always fun when you actually do shoot the trouble and fix the problem.
Nice video!You will want to be very careful with reverse polarity. DC motors don't mind which direction the current is going. Most circuits won't be so forgiving. I've burned out some expensive parts by mixing up power connections. Hope you do not.
I had placed a diode to avoid the reverse current.