How can I change the color on a single .dwg object after import into my drawing. 
Either move the object to a different layer with the color assigned you want it to display, or you can assign the color to the object and it will override the color setting of the layer the entity is on.
Hello John!Thanks for your advise it works well, in the past I used Rhino 5 on a Windows computer but now I got myself a Mac and Rhino. I love this program but Iām just a beginner!Regards Peter