The entire thing is now working flawlessly. I fixed a few bugs, and I will make sure this is solid, and release it either on Friday or over the weekend.
A few notes:
Pilot Number: FULL number, INCLUDING the code (so VMA434). This is because FSACARS does not send me the CompanyICAO field, only the pilot ID field. I need both to lookup who you are.
Flight IATA: FULL number, INCLUDING the code (VMA654654). I can't look up a route without that code. The CompanyICAO field is not sent to me here either, and I don't know what airline a route belongs to without the code.
Registration: REQUIRED, or else I don't know what aircraft you used. Now that there are multiple aircraft of the same type, I can only look up the registration number reliably.
To send the PIREP, you click "Stop Log". It will ask to Accept or Decline. Click Accept. Then, click the "Flight Log" tab, then click "Send Log". It will ask to confirm; say yes, and it will send.
I'll have a patch over the weekend to fix errors which prevent the flights from showing, and to upload the code to use the registration data, and properly parse the Flight IATA. If you forget the code, I can "guess" which airline is it, but if it doesn't find the correct flight, then I can't do anything about it. There will be a "Edit PIREP" option, but it might not make this weekend's release, most probably the next one after (depends how much time I have this week).
Also, FSACARS loves to spontaneously stop working (properly). Deleting the fsacars.ini file and reinstalling (the latest 4.0.15 version) fixes the problems. You NEED to use the 4.0.15 because they have changed how data is send between the versions. Their documentation doesn't match either version, so I've picked apart how they send it in 4.0.15 since it is the latest.