Storyboard QUITTING when I drag layers to new panel

Hi, new to the software, so please forgive me if I get the terminology wrong.

I create a new board panel, and then drage 3 layers from the previous panel to the new one - then it all quits. Am I asking it to process too much? Two of the dragged layers are drawn in SB Pro, and one is a oicture PNG for reference.

Running on Yosemite 10.10.5 iMac
2.9 GHz Intel i5

Many thanks for your help.

Try copy/pasting one image at a time.

Alternately, right click the layer to “share drawing” and
from the Library’s “shared” folder frag the drawing to a
a layer of the panel you want to bring it to.