The Editor that's being used in the SilverStripe CMS is TinyMCE. So there's no need to install it.
If you need text foreground and background color editing, simply add the required buttons to the editor by adding the following line to mysite/_config.php
banal, It works perfect!
Thanks for your helping article! :)
Please have a look my other questions below:
These two questions are really basic issues. The first is a pure CSS "problem" and has nothing to do with "Installing SilverStripe" (the forum you posted to). The second one is also placed in the wrong forum in my opinion. It has nothing to do with "Customizing the CMS".
That aside: You should really do the SilverStripe tutorials first. Also get yourself a book or a good CSS reference. After doing so, you'll be able to resolve your problems on your own.