Cannot get bike in gear.

I guess I'm s little confused. Over tightening the lock bolt with adjustment screw turning could possibly result in the clutch being slightly released all the time. I would not think this would affect shifting up or down.
Shifting up and down must be done with the motor running. Some foreward movement of the rear wheel may be required.

Good luck. Tim

Having to rock the bike back and forth is normal to get it into first on neutral.
Steve