Hi,
The 1.8.5 preview does now support canonical URLs.
This means that there is an additional attribute in the header that tells search engines that e.g.
http://www.tinywebgallery.com/demo/index.php?twg_album=01_Administration&twg_show=Administration+Help+Screen.gif
and
http://www.tinywebgallery.com/demo/index.php?twg_album=01_Administration&twg_show=Administration+Help+Screen.gif&twg_rot=90&twg_zs=1301827018
are the same page!
This is important to avoid duplicate content on your site. I have this now running at the demo and will check in the webmaster tools of google how this works :).
More info about this: http://www.google.com/support/webmasters/bin/answer.py?hl=en&answer=139066
Have fun using TWG,
Michael