Epervier, i have no idea, mate - as i say, i built this install from scratch a few days ago, and it was running beautifully.
then, without adding or changing anything at all, this problem started, and i don't know what's causing it....
as you say, there seems to all of a sudden be many possible issues.....but how and why, i really don't know.
i do have the two jetwar sfs files in my SAS_SFS folder, but they are not enabled in .rc file.
i would prefer to not have anything to do with jetwar in this install - all i want is Pacific theater, WW2.
even so, i have been unable to install certain WW2 planes and weapons without first installing some or other jet related thing.
anyway, i eventually added the Engine mod 2.6...does this then also need the jetwar sfs files to be 'activated' in .rc?
if so, why was i able to play on this install for a day or three without issue?
i still have a 409 install, which it is becoming more apparent to me as each new day passes, is the only truly stable install i have ever had - if it does encounter problems, they are easily solved through the common bug-fix processes.
nothing mysterious/inexplicable has ever happened on my 409 installs.
i guess it is a small sacrifice to endure a longer loading time, when at least when it does load, it is stable.
as opposed to any new DBW or Modact install, which have all only worked for a handful of days, before all falling prey to some or other inexplicable problem that each time, just appears out of nowhere, with no obvious cause, and also no obvious cure.
then again, there are several 4.11.1 only mods which i would rather not have to part with, such as many of PAL mods.
i have already lost count of how many times i have had to do a fresh reinstall over the last few months, and each time a new problem presents itself out of thin air, within a few days.
@ Gerhard, i will try some other loading orders as suggested, and report back.