The
presets dialog allows you to save the various parameters of V-Ray into a
text file, so that you can re-load them again quickly, if necessary.
Currently the presets are stored in a file called vray.cfg in the \plugcfg
sub-folder of the 3ds Max root folder.
In the left part of the dialog are listed all of the presets in the
vray.cfg file. In the right part are listed all of V-Ray's roll-outs. You
can select which roll-outs you want saved to or loaded from a preset.