I feel bad about this, but I hadn't used Spriter in a long while, or even logged in to Steam. I decided to open it today. It automatically began downloading updates. When the updates finished and I clicked launch, nothing happened - no error message or anything. I checked the task manager - no spriter. I restarted the computer and tried to launch from the start menu and from steam - No message, no spriter. I launched sprite lamp just to see if it was something wrong with launching apps from steam - sprite lamp worked. I uninstalled and reinstalled spriter. Click launch, no spriter, no message.
It says spriter pro - I'm pretty sure I purchased it as part of the Humble GameMaking bundle a long time back. I hope we can get this working.