I downloaded the chm manual and I cannot view the content.

The manual is in a chm format (Windows help file). In order to see the content, please download the file on your computer, double click on it and uncheck "Always ask before opening this file" before clicking on "Open". The other way that you can unblock the file is to "Right Click" on the file and choose "Properties" from the menu. Click on the Unblock button next to Security (under the attributes section). Next time when you open the file it should display properly.