Can't you just go to the package manager and install that one? It's been a good while since I used Mandrake but it is a binary setup. It is not really made to compile most things. It can be done but you have to take care of all the packages it needs to build. Doing it by hand is not a good idea. It would be a lot easier to let Mandrakes package manager install this.
Again, it has been a while since I used Mandrake.
One more piece if info, Fluxbox is fast on older systems. It is really basic but works. I use KDE but have it installed as a backup. Speed wise, there is no comparison.