The version you downloaded is quite old actually, and we hope to have a new release very soon.
Garry's updates to Gmod over the past year have caused quite a few issues with the way ULib initializes.
We'd love to have you visit our SVN section and learn how to help us test/use the latest code.
We understand if you don't want to though... there are (rare) occasions where SVN may work less than the release.