Rotate engine by hand while watching for the valves to open and close.
Your test of spark across the plug in open air is meaningless and has not proved that you spark system to cylinder 1 is good. It takes only 2000-3000 volts to jump that gap in open air but 20,000 volts or more to jump that same gap in a compressed fuel-air mixture.
Recheck your spark plug wire with an ohmmeter and be sure that the resistance is in the 3000-5000 ohm range. Examine the wire for anything obviously wrong. Place the end of the spark wire 3/8" from a metal surface and crank and see if the spark will jump that large gap in open air; that is the only valid open-air test to do.
Swap plugs.
