Barry,
I do not quite get what you mean by the remark:
I am making files gallery independent.
Can you explain what you mean?
Your questions:
1. SVN access: you can get anonymous access to our SVN repository at
http://scm.joomla.org/svn/repos/rsg2. Just take an SVN client and you will be able to update from SVN. Obviously you won't be able to write into our SVN.
2. We are always interested in improving our code so we are certainly interested in your modifications. We try to comment the code as much as possible but if you any questions, just post them in the General Discussion Forum. Also the
API might come in handy.
Good luck!