The challenge with supporting Type B photometry is created by a bug in Revit where the photometric web graphic displays incorrectly in the Revit model. When you have a Type B photometric file, Revit rotates the photometric web by 90 degrees for an unknown reason.
ElumTools, on the other hand, uses the LM63 specification to determine how to display the Photometric Web in Luminaire Manager, and how the light source should be rotated in the calculations. This creates a mismatch between ElumTools and Revit. The photometric web may be rotated properly for ElumTools purposes, but Revit will display it incorrectly, or vice versa. So Type B is unsupported for ElumTools, to avoid confusion.
Type B photometry can be used with ElumTools calculations if the Photometric file is assigned outside of Luminaire Manager. You can assign the IES file directly in the Revit Type parameters as shown below. Revit will rotate the photometric web incorrectly, and Luminaire Manager will say "Unsupported Photometric Type", but as long as the Photometric web appears aimed correctly in Luminaire Manager, the light source will be aimed correctly in the calculation.
The other workaround would be to convert the Type B photometry to Type C. This can easily be done using