The footer widget area is handled differently in Xtreme.
Weaver II was limited to 4 side by side widgets. Xtreme has no limit in number size or placement.
The way you populate the footer widget area in Xtreme is put as many widgets in the footer widget area as you want, then decide on the layout in Main Options > Footer > Footer widget area.
In Xtreme basic, you basicallt set a number of columns.
In Xtreme with “Plus” you can define any layout you want and can can set a different layout for each device size as explained here:
http://forum.weavertheme.com/discussion/10342/weaver-xtreme-tips-and-tutorials-part-1