Hello Linux Geeksters. As you may know, KchmViewer is a KDE application for reading chm files, written in C++ and compiled against Qt. Being desktop environment independent, it works on other DEs except KDE. (I have tested it on GNOME)
The latest version available is KchmViewer 6.1.1, which has been recently released.

In this article I will show you how to install KchmViewer 6.1.1 on Ubuntu 14.04 Trusty Tahr, Ubuntu 13.10 Saucy Salamander, Ubuntu 12.04 Precise Pangolin, Linux Mint 17 Qiana, Linux Mint 16 Petra, Linux Mint 13 Maya and Elementary OS 0.2 Luna.
Because it is available via the GetDeb repository, installing KchmViewer 6.1.1 on the listed Ubuntu, Linux Mint and Elementary OS systems is easy. All you have to do is add the ppa to your system, get the repo’s key, update the local repository and install the vuze package.
Follow the instructions for your system exactly, in order to get a successful installation.
How to install KchmViewer 6.1.1 on Ubuntu 14.04 and Linux Mint 17:
$ sudo sh -c 'echo "deb http://archive.getdeb.net/ubuntu trusty-getdeb apps" >> /etc/apt/sources.list'
$ wget -q -O- http://archive.getdeb.net/getdeb-archive.key | sudo apt-key add -
$ sudo apt-get update
$ sudo apt-get install kchmviewer
Optional, to remove kchmviewer, do:
$ sudo apt-get remove kchmviewer
How to install KchmViewer 6.1.1 on Ubuntu 13.10 and Linux Mint 16:
$ sudo sh -c 'echo "deb http://archive.getdeb.net/ubuntu saucy-getdeb apps" >> /etc/apt/sources.list'
$ wget -q -O- http://archive.getdeb.net/getdeb-archive.key | sudo apt-key add -
$ sudo apt-get update
$ sudo apt-get install kchmviewer
Optional, to remove kchmviewer, do:
$ sudo apt-get remove kchmviewer
How to install KchmViewer 6.1.1 on Ubuntu 12.04, Linux Mint 13 and Elementary OS 0.2:
$ sudo sh -c 'echo "deb http://archive.getdeb.net/ubuntu precise-getdeb apps" >> /etc/apt/sources.list'
$ wget -q -O- http://archive.getdeb.net/getdeb-archive.key | sudo apt-key add -
$ sudo apt-get update
$ sudo apt-get install kchmviewer
Optional, to remove kchmviewer, do:
$ sudo apt-get remove kchmviewer