I've been working to get a functional development build ready all morning. It turns out that there were two issues to be addressed, due to changes that Michael and the SwS guys had made in the NetResources library, and in WithStyle itself.
First off, the NR libraries had eliminated all references to the Twoflower HTML parser. As it happens, the replacement parser isn't ready for that step yet - there's lots of HTML it doesn't handle yet, so the result was content that we couldn't display unless LibTidy (A C library) did it for us. That was a problem, and I addressed it by making the relevant code invoke the old Tf parser as a last resort. Voila - it works!
The other problem was due to API changes made in WithStyle. I've implemented a parallel API for document loading in the Blog poster - the default API forks a few processes, and I wanted to be able to catch exceptions (and toss the poster into plain view mode) if a downloaded post was just too messy to handle. I did that quite awhile ago, and there were a few subtle changes in the latest WithStyle code that nuked my API. So, I walked through it again, patching it back up. I'm using the poster now, so clearly it's working again :)
I've got the new build uploading now, and it should be ready for download later today. Mind you, this only matters if you downloaded a full development build in the last few days - if you haven't, you should be fine with what you have now.