The structure looks very similar. The indi-dsi and indi-sbig actually were attempts, but failures, so you can ignore them. As I recall the only thing I had to do was the configure and make step in the gsl folder and then it worked from there. I don't think I had to build the others. But Adam reported that this worked fine on OS X El Capitan, but he had trouble on Sierra. Did you read the post he just sent about it?

That's what I wrote above. You can install libnova with:
brew tap polakovic/astronomy
brew install polakovic/astronomy/libnova

The approach of just placing the folders in the directory doesn't really seem to work (at least for libnova and libusb).

Ok, then we will change that in the instructions. I don't know how it worked on mine then. Who knows? I only did it once.

Finally got to try this now, installing qt5 takes a VERY looooonnnngggg time lol....

You are not kidding! You can just leave it overnight and then sometimes it is not done even then.

aaaaaaaaaaaaa, and I thought it was my machine, Glad to hear it's normal...
Off to connect the charger

Nope, I want to say it takes maybe 6-8 hours? I don't even know.

after hours of waiting:

zError: No space left on device - /Users/stephane/Library/Logs/Homebrew/qt5/02.make

That does not sound like a good error. . .is your hard drive full or does your hard drive have bad sectors? You might want to run fsck?

I have 18G of free space... good drive, no issues.

One thing you could also try is the qt5 patch mentioned earlier (and also in Rob's instructions), because it excludes some modules that don't seem to be needed by kstars anyway (at least it worked decently for me). Using the patch decreases build time and probably also the disk space needed during the build significantly.

is there really a need to brew install qt5 ?
can't we use the dmg file: download.qt.io/official_releases/qt/5.7/...5.7.0.dmg.mirrorlist