I would place this vi under the "My Computer" cluster in the project viewer instead of the vi that is on the myRIO. Is this possible? Can I run the queue between two vi's?
So I was correct with my initial guess! You have to treat the myRIO like it is a separate computer, because it is. NI does a great job abstracting this concept away, but it bites us constantly when File IO is encountered.
What you need to do is make an application on your PC that just gets data from the myRIO. How to get the data? I use the STM library to communicate over TCP/IP. Many around here really like Network Streams. Either way, you need to have your myRIO connect to an application on your PC and use that connection to send the data. The PC application can then log the data to wherever you want.