> I use third-party DLL that I was told was written in VB (by a salesperson?), and I get to it in VB via a DECLARE statement and function calls. Does this mean that particular DLL was written in something other than VB (probably C++)?

I'm far from an expert on VB (VFP and C++, usually), but the only options for creating a DLL that I see are for ActiveX (COM) DLLs. Based on this, I'd say you're not going to get exported functions out of a VB DLL. I could be wrong on this one, but odds are it was written in some flavor of C++.