Scopes and Curves

How so I superimpose curves from multiple runs in a scope?

Scope blocks have a Window options parameter. Select 'Overlay' for this parameter to layer curves from multiple runs in a single scope.
Figure 1.

Example of curves from multiple runs overlaid in a scope block:

What are some best practices for scopes?

Use External Activation

By default, scope blocks inherit their activation. If you want to control the scope activation, and as a consequence the number of ports through which the scope can receive activation, select the External activation option on the scope.