The rewritten version of HLib has just been checked in. HLib is now compatible to IE, IE Mac, Mozilla and Netscape 4. New features are: a framework for animation, rpc, io, flash support and some new visual components.
The current sources are a bit outdated (for example concerning IE 6 compatibility). An update is in the pipeline. Expect the new and heavily improved version (including RPC/IO, animation system and new widgets) in 2-4 weeks.