So clicking on the headers of each category (Icon Theme, Icon Size, etc) does not collapse the other panes?
Depending on the versions of Jquery UI and WordPress in use, the Jquery accordion tries to set the height of the open tab to 100% of the window height of the browser. Looking into a permanent fix for this, but since Jquery UI is a third-party, a solution is not easily created as a work-around.
As a temporary solution, you can try zooming out in your browser to access the other tabs, then click on the each header.
Updating to the latest version (1.6.2) will fix the height issue in the Widget/Shortcode Designers.