i like to keep it simple the less I have to do the better, to be Honest
Here's what I do:
1. Using a program like SimStarter or any other 3rd party program that can automatic load(inject) a flight plan(.pln) in the SIM
2. Start the weather program (OPUS or ASN) BEFORE you start the SIM. Please note you have to 'tick an option in ASN so it will auto load the injected FP. OPUS does it automatically.
3. Use Simstarter to start the SIM and autoload the FP.
That's it, you will be sat at the gate, not just with real weather but also your weather program will have auto loaded the route and you automatically have the complete weather for your route. Just like in your OFP
All that with one press of the button.
It's the way to go to be honest. If you can get PF3 to 'inject the loaded FP, that would be good.
Any questions then please let me know
Clive