200FT Hard cold start. Pulls like a train when warm.

[TonyS9]

So you have checked alot of stuff and I can see the semblance of diagnostic procedure, probably limited by equipment, however I don't think you have determined the basics of fuel, fire or air (which one).

Brainstorming;

So if the ECU is reading the correct temp is should be directing lots of fuel to the engine, so it 'should' not be a fuel problem, however perhaps there still is a pressure problem at cold. I'd like to measure rail pressure, incase is an unusual temperature sensitive failure. FPRs are a common fault, also you need feed and flow from the in tank pump (assuming 2 pumps), when the main pump will show dead end fine, live rail pressure will direct you in the right direction.

Air is decided by the idle valve mainly, is it operating well? Pull it out and look at it when you turn the ignition on (keep plugged in). Is the throttle closed switch working?

Does opening the throttle help the starting?

Sparks, is the rev counter needle flickering during this non-starting, after TDC pickup (takes maybe 1-2s)? have you a set of spark checker lights just to eliminate? Ignition amp can have temp sensitive problems (usually hot running problems).
The rev counter trick is a great initial diagnostic checker on the ignition system. It uses back emf from the coil, so checks for ECU, Crank sensor, ignition amp and coil. Spark check lights are the final check.