Hello Fubar, I'm a little confused, and will try to explain why.
1) Cellinsky's Readme says to copy his zipped contents (which include several cloud files and an Environmentalsystem file) to the "\StrikeFighters\Flight\" folder. However, when I open the FirstEagles \Flight\ folder, there are no pre-existing cloud files nor an Environmentalsystem file to replace in that FE folder.
2) The First Eagles Environmentalsystem.dll file resides in the \System\ folder, but that folder also doesn't contain any cloud files to replace, and in fact, I can't find any cloud files in ANY folder in FE.
3) In your directions you state: "\WWI\Flight[/p] folder" and I'm not sure what the "[/p]" is about. I don't think it is important, but just asking when I don't understand for sure.
I'm probably just being overly cautious and perceiving illogical placement of these files, when in fact there is a good reason to do it as explained. I'm learning to implement these types of modifications for the first time and trying to understand why things are going where they do. It is really very interesting to be inside the game itself, and shape it to some degree. Thank you for you work, please let me know what's up.