The base address of DLL are different by language each other.
If you install English version extended kernel to other language version Windows 2000, it may be gone BSoD :3
http://blog.livedoor.jp/blackwingcat/archives/1880785.html
XP version was changed for supporting for XP
* InitializeCriticalSectionEx replaced InitializeCriticalSectionAndSpinCount
* Remove SetThreadStackGuarantee thread
* not use RtlGetVersion
Why don't you think about it the other way around?
NT4 don't have DisplayMonitor API .
So any application should be changed not to use Display Monitor APIs or be able to Ignore these APIs.