I've tested this some time ago, and it did not work...
I think OFP has very specific interpreters per code, for example you can
preprocessFile any kind of file (any extension) and call them later...
For example I have preprocessed and called (or call loadFiled) files with the next extensions (in addition to .sqf):
.ini, .cpp, .hpp, .h, .cfg, .sqs, etc...
They work, but the downside is that no matter what the extension is you still need to use the scripting commands and .sqf syntax, so if you for example preprocess and call (or call loadFile) a .cpp it will not work if it's regular .cpp...
Also, you can use the regular "" exec "this.sq
f", but then the .sqf needs to use the .sqs syntax...
So it's very likely that when the *.ext interpreter finds some class in the .ext that the interpreter has not been 'told' how to deal with it will just ignore it...
I tried this by making a new vehicle class in the description.ext and trying to camCreate/createVehicle it, but no luck there...
The positive note (and the fact on which I base that interpreter assumption above) was that OFP didn't CTD or give any error, but no such description.ext 'configged' vehicle was available for creating...
But, if someone has different results, do tell...
This could open a few more doors if it worked...