>1) what is the actual name of the .ocx that each of these is installed in? and are they both installed by default on Win 7 or 8?

OLEObject = C:\Windows\SysWOW64\MSCOMCTL.OCX

On my Win7 system this was installed and on a Win8 system that I support. Not sure if this is always the case.

>2) where did you get your documentation so that you could use them effectively?

I have not created any documentation -- use as is. They return an object with two properties:

loFileNames = CREATEOBJECT("Empty")
ADDPROPERTY(loFileNames, "Count", 0)
ADDPROPERTY(loFileNames, "List[1]", "")

The List[] property is a listing of the selected files with full path; Count is the size of the array.