>I have poured through the documentation, but see no place where all of the VFP-associated .DLLs are explained. What does each do? If anyone know where the documentation is hiding, I would appreciate also knowing.

I've never seen such documentation from Microsoft at least; my experience shows there to be three very broad categories of functionality provided by the VFP-related .DLLs:

VFP runtime environment: These files (in VFP 5, VFP500.DLL, VFP5ENU.DLL, VFP5ENV.DLL and VFPOLE50.DLL) provide the VFP runtime environment and data engine. These files are the base engine; I have no idea exactly which functions are associated with each module). Also included here is FOXPRO.INT, which provides internationalization resources for FoxPro message boxes, errors, etc.

General ActiveX/OLE Automation components: These files provide the common runtime environment for all ActiveX controls and OLE Automation servers, both clients and servers. ASYCFILT.DLL, OLEAUT32.DLL and OLEPRO32.DLL are the common providers; these are common components for most Microsoft products. The common .TLB descriptor STDOLE2.TLB is also included in this group

MS compiler runtime environments: Microsoft puts some common functions used by applications compiled with their C/C++ languages into some standard .DLLs; some of these are operating system and operating system version sensitive. At least look, a number of the Visual C/C++ libraries were required (MSVCRT20.DLL and MSVCRT40.DLL) and the NT-specific version of the 3D Controls in-process server (CTRL3DNT.DLL; I think that 95, 98 and NT 4 have the base functionality always present, so it's there for NT 3.51)