Ahh yes, that is partly my fault. I should've been a bit more clear. The .gstencil is for versions of omnigraffle prior to 6. Sorry for the confusion. You can

Ahh yes, that is partly my fault. I should've been a bit more clear. The .gstencil is for versions of omnigraffle prior to 6. Sorry for the confusion. You can download a trial of omnigraffle 6 and then export the stencil as an .svg