How can I make the radioactivity module works in Drupal Commons?

Radioactivity is a spettacular Drupal module which provides a sorting criterion based on the "energy half-life" concept.

This is a quote from the official page:

The Radioactivity module provides hotness-based popularity metrics to nodes and comments. The fundamental idea is that when objects have some activity, they heat up. At the same time the objects also constantly cool down at a rate proportional to how hot they are. So, the objects that have more current or recent activity stays hotter than the more inactive ones.

I installed Radioactivity module on a "Drupal Commons" (social-network-like) configuration and it seems to work fine except... the energy is static (there is no time-dependency), in other words there is no decay at all!
Even if I still use default settings (granularity = 600 sec; Half-life = 21600 sec).

The concerning site is http://www.democraziadiretta.net/
The idea was to have this 3 column grid with all the featured content sorted by the "energy" value provided by the Radioactivity module, problem is that this module won't work in the drupal commons contest, and I just can't figure out why...

Anyone here knows I can I fix it, please?

I made the same question to Radioactivity module developers here: http://drupal.org/node/1021766 but no answers so far.

Thank you.

Duccio