The special effects worked with the 1.4 patch, but the oil-leaks did appear and disappear, I think it was the solution Dave and Is4htl came to, because they couldn't solve the issue with the tool that existed at that time.
The appearing and disappearing happens now on my 1.5 installation, so if the file you send to me Nisgeis works with 1.4 (can you confirm that Dr. Beast?), then my guess would be it have something to do with the way the U-boat missions handles the particles / materials.dat?
It seems we are close to a solution,thanks for working on it!
EDIT...Or Maybe we need to make two versions, one for the 1.4 patch and one for the U-boat missions?