Costumize the order of the Tag Cloud words

Hi
I would like to organize the words in the tag cloud differently to the default. The words are organized alphabetically, but i need to organized by period of time.

I added a plugin: “Category Order and Taxonomy Terms Order” which helped me to organize the Portfolio categories. However when the portfolio categories are displayed on a widget they get organized again alphabetically.

Here is an example:
http://daghlian.qc.cuny.edu/portfolio_entries/neolithic/
On the right, in the “DYNASTIES” widget, i need to place Neolithic as the first word. How can i change the organization of the words?

thanks!