Just so you know, ⌥; is only the keyboard shortcut for U+2026 HORIZONTAL ELLIPSIS in a US keyboard layout. To steal from arm’s comment on Hacker News:

“Of course, Apple’s advice for typing U+2026 HORIZONTAL ELLIPSIS (…) (typing ⌥;) is only accurate if you’re using a US keyboard layout. The key combination will be different in other keyboard layouts. For example, in the 'Canadian French - CSA' keyboard layout, typing ⌥; will give you U+00B0 DEGREE SIGN instead (which makes sense if you actually look at a French ISO layout keyboard, like this one or this one). On that keyboard layout, to get U+2026 HORIZONTAL ELLIPSIS, you’d actually type ⌥⇧L (option-shift-L).”

Also:

“Hah, this is interesting. MacHeist just added PopChar X to their bundle, so I tried it out, and I was surprised to find it actually shows the keyboard shortcut for your selected character (if any exists) based on your current keyboard layout. That’s pretty convenient.”

Taken from this comment thread.

Hi Brett. Can you comment on how you differentiate between "Arrange By" and "Sort By" options? I'd like to map a few options as you mentioned, but only for sorting (I don't care about grouping). However since they have the same names under the two menus, and the default one is "Arrange By" (accessing sorting requires Option pressed) I get the mappings applied to grouping only. Any idea how to map, say, "sort by date"?