Hello Felipe
for some reason it seems my account dissapeared and it did not let me post, anyway i created a new one, I didn;t want to post it because its a mess, but I have recently successfully installed it from the tutorials in the files themselves.
I think this should be known by all newcomers, so if there is a way to bump this post please do ^^.
so as long as you can get the files from the git repository (i.e. git clone git://openfoam-extend.git.sourceforge.net/gitroot/openfoam-extend/openfoam-extend OpenFOAM®-1.6-ext)
you are fine, then open the folder go to:
/doc/buildinstructions
then pick your OS (ubuntu for us, there is also centos and openSUSE, and follow the file for your installation, and your done! ( I have 64 bit laptop so i guessed that you may need an installation for a 32 bit one).
hope it helps
Kiyo