UBB.threads PHP Forum Software Community Forums UBB.threads Importer Support members dir error on import

To keep a long story short:
Oldforum (classic) is running on an old server and old domain.
Newforum (treads) is installed on new server and new domain.

So what i did was: copyd the old dirs (as of a back-up) and put them under the new dir on the new server.
So the new situation looks like this

Root(new server) - My Web DIR -
.Forums(Treads)

.OldForum(Classic)

.. UBB

.. UBBCGI

... Members

btw: old forum is closed now and will be reopened as soon as newforum is operational.