See if this helps with sharing folders: LimeWire 5 - Adding folders to library, sharing/unsharing files, removing folders - Windows.

And for changing the download location - as well as choosing your download folder within tools > options > downloads, just check where specific categories are being saved.

In LW go tools > options > advanced > files. Click on the Configure button next to Download Folders. Check the locations of saved folders for the different categories & change them if you have to. Click ok to save the change & then click ok again on the main options page.

Genre searches may be coming in future versions: Genre - LimeWire Forums

I think I have Java 5, So It won't work?

No, you'll need Java 6 to run LW 5.

You can update your Java here: Java SE Downloads - Sun Developer Network (SDN)

Use the JRE offline installer (less chance of corrupted installation when installing offline) & remove any Java versions already installed before you install the new version.

I hateeeeeeeeeeeeeeeeee java. But its a must for everything.