I just built a HFSPLIT non-english w2k CD using http://www.vorck.com/2ksp5.html guide (kept IE5 for now).
during file copy step (right after partitioning step), comes a file not found on CD error for a few files wuapi.dll, wuactl.exe, wuauclt1.exe, wuaucpl.cpl, wuaueng1.dll, wucltui.dll.
I figured out the problem comes from WindowsUpdateAgent20-x86.exe hotfix. So I removed it from \HF directory and rebuilt a CD which worked.
So I decided to check the faulty CD build for those supposedly missing files, and I found there were all present but with a wrong extension.
wuapi.dll.mu_
wuauclt.exe.mu_
wuauclt1.exe.mu_
wuaucpl.cpl.mu_
wuaueng1.dll.mu_
wucltui.dll.mu_
then I expand the WindowsUpdateAgent20-x86.exe hotfix and found out the it contains multilingual files
wuapi.dll.mui_xx
wuauclt.exe.mui_xx
wuauclt1.exe.mui_xx
wuaucpl.cpl.mui_xx
wuaueng1.dll.mui_xx
wucltui.dll.mui_xx
where xx is a 2 letter code for each language.
I also found that each file also exists with the regular extension in a \xx subdirectory
I makecabbed those and replaced them in the \SOURCESS and build an ISO with nlite 1.0RC6 and the file copy failure is gone.
-edit-
I just figured out I could use the \FIX directory and put those makecabbed file inside it.
definitely a good idea to include such a directory.