The game is not available.
What we've* managed to do is get two programs working from the Issue 24 Client:
-- Titan Icon - A machinima toy to let you explore zones and create NPCs to animate (using console commands) if you want to make COH videos.
-- Paragon Chat - A XMPP Chat program using the Issue 24 client files to allow veteran City of Heroes players to meet up and talk to each other again. Paragon Chat is exactly as it sounds, a chat app. It isn't a game, although we got parts of Paragon City working again, including badges and ski slopes.
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* 'We' used in the 'royal we' sense at Titan Network. All glory to the Hypnotoad! Er, um, I mean Codewalker and Leandro, the actual programmers of Paragon Chat.
I'm not a developer myself.