Hi BP.
I don't have the game, but if the file-structure is the same as Il-2, then this may be determined in the.eff files (which you can open in note-pad). If this is the case, there will be written lines followed by numerical values. The values may determine, for instance, opacity, the transition time of the effect, how long the effect lingers etc.
In Il-2, many of these lines were found to have been calibrated in way which didn't give optimal visual aesthetic (for instance, looking at videos, some smoke effects in CloD just disappear without dissipating. I don't know if this is a bug, or if the effects-modellor got lazy with the parameters).
I don't know if you are able to find these files or not
