I mailed a simple example to Victor Victorov, the 9rays support man. Still had no response, but the above reply says it all. In the examples provided by 9rays, the editor attribute is always applied on the entire type; not on separate properties. So, I'm really looking forward to the next release because this is (or can be) quite a handicap for many developers (especially for me ).
For those who cant wait; a workaround:
During grid buildup; you can check the property attributes yourself, and based upon this, create CustomDropDownColumns, or whatever (inherited) columntype you wish. Since this way of working requires you to do a check for each and every type/contents of propertyattribute; it implicates a little bit less flexibility. My opinion is to wait for (the hopefully very soon to be released) new version, since the editorattribute-way is the most .NET charakterized way (and the most flexible, elegant way).
Anyways, thanks for the reply!