The best ways to change the color scheme are from Chime's Colors menu, or by issuing commands. Pressing the [Model] or [All] buttons does not change the color scheme, so whatever colors you apply will be preserved during these operations.

In order to customize the rendering produced by the [Model] or [All] buttons, modify the script in the box labeled NMR Model Script. In this script, the symbol @ will automatically be replaced with the current model number (or all). For example, if you enter "12" in the Model slot,
"select model=@" will be converted to
"select model=12" before it is sent to Chime.

For example, a script to render each model as a cartoon would be:

restrict model=@;
cartoon;

If, in addition to rendering protein as a cartoon, you wish to render hetero atoms in ball and stick, the script should be:

restrict model=@;
cartoon;
select model=@ and hetero;
spacefill 0.45;
wireframe 0.15;

Whenever an Always show model number has been entered, a custom script will be ignored by the [All] button (and in the initial view following entry of a model in the Always show slot, which uses the same [All] function). The custom script will, however, be employed by the [Model] and [Auto] functions.