MikeB4: Have a look here
http://www.tenforums.com/tutorials/2570-esd-iso-create-bootable-iso-windows-10-esd-file.html
Thanks :) My W10 install is pretty borked, I'm not even sure it'll download the latest build. Event viewer won't run, uploading files using any web browser locks it up more often than not, etc. I guess I'll just get the latest ISO and then upgrade from there.