nevermind I figured it out. I had imported with 'new' selected and wiped my UV's. Imported again and all shells are dropped to UV mode and now 3D mode cut and weld selection does it like it always has ...
In the totorial video 'welding shells', you have a section where you cut edges you select in 3D mode. I cant do this, I cant select edges hitting 'c' or 'w'. Has this been taken out of UVLayout? Or is ...