I added blind/buried via capability to the Copy/Paste routines. I've used it successfully on one design which I am translating from BSRE to Expedition. So far so good with one minor issue - not all traces/vias come across if you select them all at once. Going back later and selecting individual nets or just a few does the trick. It was the same before I added the blind/buried stuff, so it might be something else.
I've attached a zip file that has the copy and paste scripts. They go in the AATK_V4.0\vbs\CopyPaste directory.