I created a new download that includes a tiny update to Risen. I have been googling and doing some brainstorming and came up with solutions to a few things that have been bothering me:
1) I was able to add trees to the scenery in isometric view. This sounds simple, and the solution ultimately was, but it took me a while to find the answer.
2) I was able to add windows to the buildings in isometric view. Another tricky thing. Took some extra photoshopping.
3) I was able to unencrypt the file so others can look at it. It was originally encrypted because I had some paid-for plugins that I couldn't distribute. But those are gone (and were causing conflicts anyway, so a good solution all around).

I also made a few tiny changes and improvements to skills, enemy placement, hero placement, and some tiny dialogue changes.