While I will agree that there is great information there I am not sure it has been updated for SF2. I, for one, was extremely frustrated by the lack of information regarding the move of the aircraft files from the root program folder to the users My Documents folder. The other frustration is that EVERYTHING has been packaged in CAT files unlike the original titles. The SF2 CAT files are in a new format that requires a different utility to extract (found in the downloads section.)
Hubertus, you might want to look through the articles in the KB (remembering that your new aircaft will go in you My Documents\Thirdwire folder) and then stop back with specific questions.