The answer to your question is Yes, you can. The Husqvarna software let you design stitches for your machine to be used in the sewing mode and as a fill stitch in digitising an embroidery design. You can upload it to your Ruby per USB stick. I have a couple I downloaded from the Husqvarna website (from their monthly newsletter, some Christmas designs) and some I digitised myself and I use those in the sewing mode.
I had a look and found an article on making decorative Motifs. It was for 4D or 5D but works the same in 6D.
And there is also a newer more concise one for 6D. In both cases choose Module Mystery in the Newsletter.
Thank you. The links were very informative.
Can we create dimensional stitches too?