Why don’t you support the older versions of ____ render application or plug-in?
In general, it is not necessary or constructive to do so. The majority of the time, scene files created with older versions of applications and/or plug-ins will render successfully and identically in the newer versions of the same software. For example, if you create a scene in 3D Studio Max 2012, that will render just fine in our Max 2015 instances.
There are occasional departures from this behavior, some of which are known. Scenes that use the V-Ray render engine, for example, must pay close attention to the version used to create their scene file. Chaos Group seems to want to live up to their name by making small changes in the way lighting and coloring work between even minor point releases of V-Ray. Small changes in the Arnold and Renderman render engines have also produced backwards compatibility issues. We encourage you to run the exact same versions of software we run to guarantee we deliver the results you expect. We post our version numbers of all deployed software in our support portal to enable you to check this.