AGAIN: Problem with PTFs for Integrated Netfinity Server V5R1 + W2K

Hi all,
I searched IBM databases up and down - nothing !
We still got the problem with 5722WSV - Windows NT/2000 Integration
on a model 820 with V5R1, Cum PTF  level C2134510.
When I look at the ptfs for the integration software for Win2K
(5722WSV option2),  I see all PTFs correctly installed up to the most
recent SI06321, but when I switch to the Win2K side and do a lvlcheck
with the MMC-Snap-In to check to Integration PTFs, I see only ancient
PTFs installed (SI01263) , the available level on the AS/400 side seems
to be of the same level and there is no possibility to install or uninstall
this package.
Is there a way to force installation of the new packages, or to force
de-installtion of the old ones to begin from new?
We have serious problems in shutting down and programmatically restarting
this server, especially for the night job.
I already tried to map a drive to /QIBM/NTAP/....service pack directory
where I tried to install one of the newer .MSI-packages - no success, it simply
does nothing ! It does not start an installation !
I installed Win2kSP3 then, to see if this is of any help (before on SP2), but
again: no success.

Any help is appreciated, thank you, Philipp Rusch