Install LXQt / LXDE-QT via PPA on Mint 17.1, Ubuntu 14.04, Xubuntu 14.04 ...

$ sudo apt-get install software-properties-common
$ sudo add-apt-repository ppa:lubuntu-dev/lubuntu-daily
$ sudo apt-get update
$ sudo apt-get upgrade
$ sudo apt-get install lxqt-metapackage lxqt-panel openbox