.dll Files you can edit with Reshack/
Much as i know resourcehacker can completely decompile DLL's and EXE's
Looked for a bit for something for you're .VFS files, this is all i could come across. http://www.fileinfo.com/extension/vfs
Nothing really looked like it helped, but there's still the link.
As for the ii2. it seems pretty unknown on the internet. File Extension .II2 Details
Some sort of install file.