Hi John,

The problem, somewhere you pickup (HV) *noise* from the sparkcap / sparkcoil / HV-coil.
Have you placed a 100nF capacitor right between pin 5 and 14 of the pic at the bottom of the PCB ?
Dont'forget to connect both sides to eachother, top and bottom.
Twist all wires and keep them short.

If you get also firingup without the hallsensor, that's allmost imposible.
A resistor hold the input high, only a hard low signal can make a output signal.

BTW-1, the CDI can't given a spark the first time becourse it have first calc the rotationtime.
If the rotationtime is less the advangetime (-/+1000rpm) the CDI is given a spark started where you set the easy start.

BTW-2, do you set CW or CCW right ?