Done, just cleaning up the code for the pull request. I'll have it ready in a while. The only problem (other than the speed) is that the BIP38 encrypted keys are longer than the height of the pretty notes and the font is already pretty small. The original image for the note needs changing to accommodate. Also needs to change 'Private key' to 'Private key (BIP38 encrypted)' or something. My graphics/css manipulation skills are awful, so I can't really help.