I dont know much about PCAnywhere, heck I can barely spell CPU. But if it exposes anything, its most likely a COM interface or a standard DLL.
If its COM, you can load it into .NET through Project References and look at it in the object browser (ctrl-alt-k). That will show you what objects and methods it exposes, though there wont be any help to explain it.
If its not COM but just a standard DLL youre mostly out of luck unless they have public (free) docs explaining how to interface to it.
Since you said ".CHF dialer", I assume you mean CHF is the file extension? If its a simple format, such as containing an IP address or something, then you might be able to figure out how to make one yourself using .NETs IO library.
-Nerseus