Well, the subject says it all. How about the Joomla! 1.5 support of RSGallery2?
thanks!

we are now working towards this

it is not yet possible, but we hope that the next release (1.14.0) is

we'll post in the nightly build forum about this, when the trunk can tested, so you might want to keep tabs on that one

There are a few fixes already posted in these forums. I just installed the latest nightly build (SVN 256), but this didn't fix anything in regards to the 1.5 compatibility.

Essentially you need to disable line 34 in the semantic template index.php file.

#rsgDisplay->showRSPathway();

After that everything should work, except for the navigation under the photos. I saw a post this morning regarding that, but I'm not sure I'm good enough with the code to poke at it that much. 

I have RSGallery2 installed on my Joomla 1.5 website as well as Coppermine (making the transfer from Coppermine to RSGallery2).

It works great so far from what I tested.  You are welcome to come check out both at my site (http://www.hosangit.com)

Biggest Bummer with RSGallery2 is two things
1.) Site's Search doesn't look at RSGallery2 currently (no plugin for Joomla 1.5 to allow using the sites searching capability but I have faith this will come eventually)
2.) Commenting/Rating system doesn't use what you have selected as your sites Commenting and Rating system and uses its own (I currently use Jom Comment for my site and would love to see the integration of this site wide commenting system to work with RSGallery2 as well so I have just one commenting/rating system on my site).

I highly recommend RSGallery2 for your Joomla site because its integrated more so then other browsers and its very easy to use.  It's always getting better and I do believe these two bummers of mine, will be eventually solved.