for the feature negotiation, you need this:
Razor Feature Negotiation
that forces the feature negotiation to be enabled... i haven't done very much testing with it, anyway it works well for light levels, as far as i can see
even if the feature negotiation is disabled...
It seems, anyway, to have a flaw: it is supposed to disconnect you if you don't have the latest razor installation and the feature negotiation is turned off, but, even if it sends the warning message, and seem to work on the light levels (only test i've run), it doesn't disconnect you as it is supposed to do...
probably that's because of some change in the SVN? not sure of it...
if someone with higher scripting skill could fix this for SVN, i would be grateful