There are many setting parameters but it can give you headache when things like it happen because you don't know which parameter will fix/affect it.
Maybe the extension needs more simple interface, for admin backend. The front end I think is well designed.
1) shadows - mostly this is caused by template - if you visit Phoca forum - http://www.phoca.cz/forum you will get quick info how to modify the template to not be in conflict.
2) admin interface - it is a Joomla! interface, so maybe this is more a question on Joomla! developers.