I was having the same problems. I managed to get the input channels working via the sample programs, (progams>National Instruments>NI-DAQmx>examples>labview 7>dynamic). where you have to choose your channels type in "dev1/ai0(1..2..3 whichever channel you're using) rather than clicking on the browse button. I am still having trouble getting the ao programs to work. Peter, I'm interested in the program you posted however I don't have Labview 7.1 only version 7.0, I don't suppose you have a V7.0 compatible version?
Kyle