A) What browser do you use?
I see the images centered in FF 2.x and IE 6.x
B) I'll document the css code for the next release (see C)
C) I think I'll make an update this week since I've added a pagination.
Now it is so, that if you have a lot of pics they are all shown on one singe page.
In the new version there will be a pagination (see http://photoblog.flanisoft.at/index.php?x=browse