OK, so I was having the problem everyone seems to have with the 500 internal error, when I first uploaded roundcube. Eventually, I deleted the .httaccess file from the main directory and the 500 internal error was replaced with your standard crazy computer jibberish.
Ex:
�������tS]o�0}�W��IM\�Z�!a�@�J*���Sd�K�ձ�m����N`j��%����sO��x>J�?LPi+� o�w#�B�z#B��}��OQ7�@���p˕���� #\Z����v�*]�tA����0�/�!� Zq�p_ i�wh���� �����r+`�P�F�%�\�(B��b��I� .���`.�1*5� �ϙ��9� #�ҔJ�|cϕa�����=S�"/E�?7|�`�Ƃ��'�� Y�4}��T��cz|jXL��ھ �����k��VK�^��A3�۳_~�lMmu^��9�N�lW������J�"[)� ��F�? �'R�X&��YG(ʸ,:�i�a�q�-B���B��- w�T��sƷ�3g w b^���?[���3E&T�ÃÂ,Ã,µ,0�qf�w�.����iw�b*\��E� �'G�ĵ=u�י�%�xq���QEu�et�D7V�5&.{(�87��J��`
I thought maybe there was a conflict with the /config directory and deleted the .httaccess file there as well but still no dice. I think I configured all the database stuff correctly and I already changed the permissions on logs and temp. I am already running another php mysql dbase on the server and it works fine.
Here is the address: http://www.dogenjournal.com/roundcubemail-0.1-rc1/