Is it possible to create beams with custom profiles?

Yes, it is. These are the steps to create a beam from a custom profile:

  1. Create a custom profile with the _vaProfileFromCurveVisualARQ profile from curve command icon command, that will be used for the beam section profile. The selected curve must be planar and closed. Checkout this tip to learn how to create a custom profile.
  2. Create a new beam style: open the beam styles dialog (_vaBeamStyles command) and click on the New button to create a new beam style.
  3. Select the new beam style and assign the custom profile you have created from the Geometry tab.
The VisualARQ beam styles dialog with a beam style with custom profile selected. The custom profile alignment points are the 9 main points on its bounding rectange.

The alignment of that beam will be taken from the 9 alignment points of the rectangle enclosing the custom profile curve.