Hi all,
I took a look at the engine model issue and found a few things.
First of all, the existing Sea Hawk DiffFM file contains some irritating additional files, like Ar-234C, some G4M, BMW 003, two more files I could not find any trace of...
Then, as pointed out correctly before, it references the J42-P-8A from Pratt&Whitney_J42.emd, a file which is not part of the HSFX buttons.
Instead, HSFX uses the same J42-P-8A but from a file GeneralElectric.emd, which holds a lot more engines inside.
Further investigation showed that at least the 4.12.2 and 4.13RC4 buttons (10.4.4 and 11.0.0) also contain the file GeneralElectric.emd with J42-P-8A inside, so the most logical solution to this issue was to simply reference GeneralElectric.emd instead of Pratt&Whitney_J42.emd.
This works for HSFX and it works for Modact 5 and 6 too. Other versions untested so far.
Please find the altered FM file, format compatible with any game version, for download below:
https://www.mediafire.com/download/oyhblspiqhhhrwkBest regards - Mike