Anybody has an idea how to move OES 11 VM from Vmware to Hyper-V?

Of course I can "convert" using VMM or 5nine Converter, but the resulting
machine will not boot (missing HV drivers)

On CentOS it is easy to correct:

but with SLES I was not yet lucky.

I get all sorts of errors like:

mkinitrd: Can't create temp dir, exiting

and if I try to redo the initrd BEFORE move then I get:
mkinitrd Could not find map hv_vmbus/boot/

Any help appreciated