No, it doesn’t. The material editor rendering uses its own settings independent of the main rendering settings.
Could it be licensing issue? Maybe having trouble locating a license across the network (or internet -- which is my alternate server)?If it was licensing then it would happen with standard materials too, since they are also rendered with V-Ray when it is selected as the material editor renderer.
Textures might be a problem - I guess the easiest way to check this is to see if it happens if the textures are stored locally. Other than that, if you feel like it, next time you get this to happen and if you are on Windows 7, go to the task manager, right-click on the 3dsmax.exe process > Create dump file; and zip and send me the resulting .dmp file. It will say exactly what 3ds Max or V-Ray is doing at that time.
Best regards,
Vlado