Above the cb user list is the search functionality which slides out if the user
pushes the search link. Is it possible to have the search fields already slided out ?
Did you try the userlist in "searchmode" ? Since that "view" opens the search form at once, it might be a good start. Although there is an additional URL param for the searchmode, I assume that it does not "trigger" the searchbutton and form display directly. The important function or task seems to be the "userlist". Also jQuery is involved here...
The only way without core edits might be a addional jQuery/Script that triggers the same action on the regular URL... or on that particular menuItem.
I am interested about your experience with that product! Maybe you can share some information and/or screens with us... ?!
I remember there are 2-3 similar products out there, but they do not offer a demo or detailed information. The strange answers and communication via email did not help either.