Just to add to the 'mapping should look identical years later', something interesting happened to me recently.
I rendered some initial images for a client. Quite a few materials used noise maps for different material properties. Then, my son wanted to install minecraft on my workstation, I hesitated but finally agreed - I knew I was asking for trouble and I got what I deserved.
The next time I rendered the same images - exactly the same file - all noises had a different look, like their seed has changed. ALL of them.
It wasn't too critical since it wasn't a final. But whatever caused it, must have been caused by installing other software on the machine, Max and Corona were not touched in any way.