First, since I had some difficulty installing this myself, here's how:

Get the UGC from here:
http://www.nexusmods.com/shadowrunhongkong/mods/13/?

Unzip the zip here (and maybe rename the unzipped folder to something that makes sense):
C:\Users\*current user*\AppData\Local\Harebrained Schemes\*game client*\ContentPacks
(AppData is as default, invisible, so you'll have to type it in or do something else)

With that out of the way:

Wow, not too many user made modules for Hong Kong! Caldecott being currently the one and only!
Good thig it's such a good one, really on the ballpark with the official campaigna and IMO, better than Shadows of Hong Kong.

A few notes though. It's a heist, so if you just want to play straight and narrow paladin, it's not for you.
Having said that, it's not just a heist, the sidestory/sidequest thingies add a lot of depth and content to the matter.
You will face meaningful choices with serious consequences, and not easy choices either. Just the kind of stuff I love.
Also, the story makes the most sense if you play one metatype or another, nothing preventing you going human either though.

Caldecott is made by.. umm.. dont remember but the same creator who made Antumbra, brilliant stuff that too.

So why didn't I play it and shout out when Caldecott came out? Well because I kind of dont like the matrix gameplay in Hong Kong, but I guess I'm kind of over it.

Try it out. It's awesome.

Thanks for the recommendation, I'll make sure to try it next time I install the game.