(Update: Modellus new site is http://modellus.pt there you will find the most recent information and installers)
The installers have been updated with some latest changes. A 32bit installer along with instructions for translating is now also available for download: http://code.google.com/p/modellus5/downloads/list
If you have doubts whether you should use the 32 or 64bit installer, use the 32 bit one.