Hey there- Brian here. There are definitely still some remaining issues we hope to get ironed out soon. That last script, if you simply attach it to a camera, is a hack that should make builds work on the Unity syphon client side.
<EDIT: FIXED>However, there are issues where if you say, rotate an object real fast, you might get some texture tearing while Syphon does its thing. As Anton mentioned we’re trying to reach out to Unity to get that sort of issue solved.</EDIT>
On the unity syphon server side, some remaining issues are focused around alpha channels, due to Unity’s various rendering stages and sometimes Unity not writing the proper alpha channel into the texture. On the Server side, either use a skybox and/or keep your scene’s background color cranked up high regarding the alpha channel value, and in your own Client side, if you can ignore the alpha channel, things tend to work better.
As another temporary workaround, if you never use transparent/particle shaders, It should ‘just work’, for now.