I have been experimenting with this a little bit, and one alternative is using the LabVIEW ActiveX API. Search the .chm's for AvtiveX.(help -> vi-function & how to help)
You also need PythonWin, look at www.python.org
Basically, delivers a bunch of nice and usable functions. I think.
digging more into creating dll's throw a search in the help-file mentioned above and search for "Building a Shared Library", or search dll and it will probably be on the list...
/Andy
p.s. no guarantee, I am a beginner just stepping into this exciting world!