Bo. The easiest method is to convert your files to 16bit tiff in silkypix and load into DSS.
A better and slightly more complex method is to install dcraw and convert your RAF files to 16bit CFA monochrome tiff and load into DSS.
This link may be helpful
http://www.guillermoluijk.com/tutori...w/index_en.htm
The options are
dcraw -4 -o 0 -D -t 0 -k 0 -H 1 -T your.RAF