Here the comments of my helper:
All of the following was done on an up-to-date Linux Mint 18.1 (amd64).
Mint indeed uses the ubuntu packages and takes most of its software from the ubuntu repo's. This is true for scribus, at least:
$ apt-cache showpkg scribus
Package: scribus
Versions:
1.4.6+dfsg-2ubuntu0.1 (/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_xenial-updates_universe_binary-amd64_Packages)
Description Language:
File: /var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_xenial_universe_binary-amd64_Packages
MD5: b9d4fea57ce9587e9ebbeb5ad30011e4
(more of the same)
1.4.6+dfsg-2 (/var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_xenial_universe_binary-amd64_Packages)
Description Language:
File: /var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_xenial_universe_binary-amd64_Packages
MD5: b9d4fea57ce9587e9ebbeb5ad30011e4
(more of the same)
Adding the Scribus PPA to the local apt sources has little effect, the PPA itself lists the "scribus" package as "Newer version available", making apt install scribus still take the package from the ubuntu repo's.
Manually downloading the .deb files for both scribus and scribus-data from the PPA does work. The fiddly bit for unexperienced users being that this requires the removal of both packages from the system before the package thingy allows you to install the package, for which it warns that it's an older version than is available in the repo's. After installing this, though, starting scribus and opening the preferences does show the color management settings section. I personally have no idea what I'm supposed to be seeing there, but I gather just having that section was the problem in this thread.
The same thing goes for the scribus-ng package, but I'm guessing the reason for this is the same.
One annoying detail with this solution is that the package manager will keep thinking there's a newer version in the repo's, marking scribus for update everytime the user is prompted to install them. Installing that update will break the color management again.
If the packages from the ubuntu repo's work with ubuntu but not with mint, it would seem some difference in the way ubuntu and mint create / package some other component in the system throws scribus off. I wouldn't know how to debug this, but I can reproduce the symptom and fix on a second mint system (also 18.1 and amd64).
Hope this info brings you guys a step closer to a (hopefully simple) solution for the curious behaviour in mint.
As for now, I'm out of town for a few days, so do not expect a swift reaction on your posts.......
Kind regards
Ruud