Scook hey! I also saw that a while ago! I wrote to XLN support about that and gave them credits to thhat great offer but still haven't heard a word... I'll try again for sure.

I've got around 3 GB in the Vstplugin-folder with DP and Session Drummer taking about half of it.
 

That is true but they come with every version so you save nothing by uninstalling and reinstaling. BTW, you can relocate the samples to free up the majority of the space those synths use. Even larger than those are the Beatscape library which came with X1 and repackaged as "Loops and One Shots" in X2.

Thanks scook! Strangely enough I found 9 GB(!) of DP in the "C:\Program Files (x86)\Cakewalk\Dimension Pro"-folder and the X2 64 Vst-plugin-manger points to that folder! This means I am running DP in 32 bits..! The Beatscape Factory Content I managed to place on an another hard drive but as I recall moving the DP-library to another hard drive resulted in the synth not finding it, as happened with the AD-drum sounds... Both XLN AD and DP seem reluctant to place their libraries on a second hard drive. 

WRT 32bit DimPro, if you installed the 32bit DimPro before the 64bit version, it will use the 32bit sample library. They are the same. It is pretty easy to tell if you are running a 32bit plug-in in 64bit SONAR, the plug-in name in the browser and menu will be appended with (32-bit) and the plug-in GUI will not have the normal VST header. 
 
The safest way to move sample libraries is NOT through the registry but using the DOS mklink command. Using either the /d or /j switch can create a link allowing relocation of any directory to another drive.

Great scook! The browser says (32-bit) allright... I surely will check that mklink command out! If the 64-bit versions can use the previously installed 32-bit sound libraries, would that go for Addicitve drums as well? I guess I have to re-install Dim Pro and Addictive Drums to 64 bit versions then since, according to other threads, the 32 bit could have caused many of the crashes I have had with X2.

Don't know about Addictive Drums. If you have the 32bit version of DimPro installed and do not use 32bit SONAR, uninstall DimPro and reinstall the 64bit version. DimPro has it's own installer. Any version included with X1 though X3 will do, they are all the same. If you use both 32 and 64bit, just run the DimPro installer again and install the 64bit version.

IIRC, if you elect to uninstall and reinstall DimPro, the installer has an option to specify the location of the multisample library.

Thanks again! Used mklink and it seems to work fine with Dim Pro and Addictive. Haven't installed the 64-versions yet though. Freed up a lot of space.