Included on the product CD is a document called FromExcel.html. This document guides you through the process of calling the IMSL C# Numerical Library from Excel by writing a wrapper in VB.NET, exposing that wrapper to COM, and then using VBA macros in Excel to call out to COM. A couple minor pieces of information (specifically about putting the wrapper assembly in the GAC) is missing from the document on the CD. Here is an updated version.

This updated version is in PDF format for easy hosting on the forum. Some of the clean formatting of the HTML version is gone because of page breaks, but I think it's important to make this updated information available, regardless of format.