Following some inquiry on support forums, we added the function of toggle username display on the Twitter button. We also addes to use the preselect styling effect medium or large delivered but Twitter directly.
That's why we depreciated the width paramater (initialy from 1.2.0) since is now useless.
This module will not more be maintened for Joomla 1.6, we are now only an 1.7 release and forward to test on 2.5.
Check all this module function and download it on this page : UD Twitter Follow Module - 1.2.1 for Joomla 1.7