Did you happen to use folder names with spaces in them?
_ Yes
Did the mods folder and install folder have similar names?
No, but i've install all the mods directly in the FF folder. I didn't maked a specific folder for them (they were in the same folder than ff7.exe & ff7config.exe)
Were you using an FF7 image to install?
No
excuse me if my english is bad, i'm french ^^
[Edit: Problem solved. I just Re-DL everything and do it one time again, but this time, i've saved a copy on my external DDE :P ]