Here is the problem.
GigaStudio was always able to stream its sounds over a network. The problem was that the QuickSound database ignored any mapped network drives and included only local drives, even if they were visible in the drive tree window. Any saving/opening of performance files were useless if they included GigaFiles stored on the mapped drive, because the performance file queries the QuickSound database for the location when open the file up.
This feature was finally promised for the 3.0 release with a different approach of the QuickSound database all together. Instead of one database sitting in the db directory of the GStudio directory, the database was supposed to be spread out and stored on each drive which was included in the search. This would also make it possible to move external FireWire drives around without rebuilding the the database constantly.

Here is the solution.
It seems that the solution is already included in 3.0 but somehow hidden, maybe for further testing. I figured it out by accident when I did some trouble shooting for some other problem:

1) Map a network drive containing GigaFiles to your machine which runs GigaStudio
2) Launch GigaStudio and you will see the mapped drive in the Quicksound tree view window
3) Rightclick on the mapped drive and select "convert to GigaFIles 3.0". This my take a while depending on the amount of files
4) When its finished , it will asks you to rebuild the database. Make sure you include the mapped drive in the QuickSound window and let it rebuild.
5) After the rebuild is finished you will see the magical plus sign next to the mapped drive, indicating that it is included in the QuickSound database.
6) Now you can use QuickSound to search for files on the mapped drive. Tataa

One downside, you can't just refresh the database, it will loose the mapped drive. You have to go through the exact procedure 3-6 again.

We have a 3 GigaStudios setup and I always was not happy of having all the sounds on the local drives - 3 times. Using the Keywords in the FIle properties is useless, because if you enter a note (great Sitar) on one machine (therefore on that specific file) you won't find it on the other machines. Having one central GigaFiles storage makes that possible. I use the central server solution already for saving the Performance files and at least that works nicely.

I did some network tests on our setup and here is what I found:

I copied our complete GigaLibrary (230GB) to a share point on our OSX Server. Yes the GigaFiles are sitting on HFS+ formated Mac drive and streaming nicely through the build in SMB server of the OSX server machine (Dual 1.2 GHZ G4)
If I'm loading a plain piano and go wild, I can create ca 250 voices with the CPU running in the 60-70% range. The Windows Task Manager shows 15% Network usage (on Gigabit Ethernet) and the OSX Server admin reports a 20% CPU load and a 8MB/s to 20 MB/s Network throughput.
The GigaStudio (3.04) runs on a Carillon box using a 3.GHz4 Pentium4 with 1GB RAM.

Let me know if anybody can confirm the workaround. I'm sure (hope) that Network feature will be included in 3.1 but until then, I'm having fun.