Hi Rob, Did you ever have any luck with the WTB file format? I need to decompile some WTB files back to XML if possible so I can get to the bottom of why my REX real time weather is sending my a2a C172 crazy above 1000ft in bad weather. I know that a a wtb file is basically a renamed blg file and I have tried using the BLG2XML decompiler on one of the stock FSX wtb files but it didn't recognise that file format. Does anyone know if a developer named 'Christian Stock' is still on the FSX dev scene? I know that some years ago he has some success with a weather theme decompiler and would like to get in touch with him. Cheers, Chris.