It's been over two months since Google started releasing Android 4.3 builds, and in all that time users of the updated Nexus and Google Play edition devices haven't been able to access the HBO GO or MAX GO (Cinemax) video services. Considering that subscriptions to both channels are pricey (on top of a cable or satellite subscription, no less) that made for a lot of less-than-satisfied customers.
Thankfully, both apps have finally been updated to new versions: 2.2.05 for both HBO GO and MAX GO. The change logs for both apps include only the cryptic "Bug fixes," but users at Reddit are reporting that the HBO GO update fixes whatever issue was interrupting streaming. I can confirm the same - the screenshots here are from my Nexus 7 2013 running stock firmware.
Unfortunately there's no real addition in functionality for either app, both of which are crying out for Chromecast streaming, but at least both apps have access to HDMI-out for compatible devices. It's worth noting that HBO's most popular shows are now available on the US version of the Google Play Store, with more shows coming soon. Cinemax's original shows aren't nearly as popular, so it may take a while for them to show up.