To run ribostral:

If you download MATLAB version:
Prerequisite: you have to have MATLAB version 7 or above to be able to work.
1- Unzip all files and put on your hard drive.
2- Open your MATLAB program and make the the folder Ribostral_Matlab\Ribostral that you just unzipped your working directory
3- Type ribostral on your MATLAB command window, and the GUI appears. 
4- To learn how to use the program consult the help file in its menu.

If you download the stand alone version:
Prerequisite: you have to download and install the correct version of the compiler (MCRInstaller.exe for Windows platform, and MCRInstaller.zip for Unix). For help with this process consult this webpage: 
http://www.mathworks.com/access/helpdesk/help/toolbox/compiler/f12-999353.html#f12-999320
1- Unzip all files and put on your hard drive.
2- Find and double click on the file ribostral.exe. It is inside the folder Ribostral_StandAlone\Ribostral by default.
3- To learn how to use the program consult the help file in its menu.