Opensnap brings the Aero Snap feature to Openbox using quicktile.

Probably. This is most likely going to be dependant on quicktile.

Just quicktile and gtk3 as far as I know. I only use Arch Linux and have not tested this on other distros yet.

Everything seems to do exactly what I want. Make suggestions.

If you want to install opensnap-quicktile. from source first make sure you have git installed. (Or fetch a zip file: https://github.com/lawl/opensnap/archive/master.zip)

Install from AUR:

yaourt -S opensnap-quicktile-git

Fetch via git:

git clone https://github.com/Pr0Wolf29/opensnap-quicktile.git

Fetch via zip:

wget https://github.com/Pr0Wolf29/opensnap-quicktile/archive/master.zip
unzip master.zip

Make sure you have all prerequisits:

sudo apt-get install build-essential libx11-dev libgtk-3-dev
I have no idea how to install quicktile on apt systems.

And finally build and install it:

cd opensnap-quicktile*
make

And now start opensnap-quicktile by

bin/opensnap-quicktile --daemon