After making an error (because device naming changed on me) and dd'ing my hard drive instead of a USB flash drive, I was able to install Deepin again (blank drive where I could put an EFI without installer not registering EFI on another drive). I hadn't had an installation since v20.
I gotta give credit where credit due, the interface is really shining and looks coherent to me (many desktops look a little scattered, this and that, etc).

Good work whomever you folks are.