Hey Andy, I'm not sure if I replied directly on these questions already but i just wanted to post responses for others to see.
Regarding // Error: Cannon convert data of type float to type float[]. This happens when more than one overridden object has the same name. for example, two lights are called directionLight1 but they are in different groups. I have revised abxRenderLayers to handle it the same way maya does, which is to apply overrides to ALL objects of the same name. (this isn't ideal and its a bug with maya, so be sure to name your objects unique anyway). So this error should be resolved in the latest version
Regarding the 2013 version. Yes the latest version is supported for 2013, although not extensively so please report any bugs to me.
Comments on this feature request:
J Adam Burke said about 14 years ago: