@terence7 “Use Nodes” should always be enabled when using Cycles because nodes is the foundation of all Cycles materials. However Blender Internal doesn’t use nodes by default (even though it can be enabled there as well).
I thought the issue was that you were creating a non-nodal material in Blender Render then switching to Cycles and enabling “Use Nodes”. Though when I try it, the color doesn’t change. So I don’t know what’s going on.
If it happens again, please record your screen when the color shift happens, post a link to your video and I’ll take a look.
