There hasn't been any update lately, mostly due to the recent focus on the iOS client. But the latest release contained a few protocol and address changes, so all bots will need the new IamFramework.jar in order to connect and operate properly. Just unzip the archive and copy the file over the old one.
Newcomers are probably best served by downloading the IamTemplate project first, which is completely self-contained and also includes the IamFramework.jar and the javadocs:
Instructions how to get started and more can be found at the wiki: http://ai.bluemars.com/wiki.
Bugs can be reported on this forum.
Lastly there's the Iam Library. It is not strictly required to download this file in order to develop Iams. But if you want to follow the step-by-step introduction that's on the Wiki you're going to need it for some of the sections: