You can follow the steps below to develop code for a cRIO FPGA on a computer not connected to a cRIO.
Note: You will need to transfer the files to a computer connected to a cRIO to be able to deploy them.
1. Open a new project on your computer.
2. Right click on your project title
>New>Targets and Devices...3. Select
New target or device 
4. Choose your device from the list. Click
OK. This will add the cRIO as a target to your project.
5. Expand the Target to display the chassis you selected
6. Right click on the
Chassis>New>FPGA Target7. Select
Deploy Later
This will add the FPGA to your project.
8. Right click on the
FPGA Target>Select Execution Mode>Simulation(Simulated I/O).
9. Right click on the
FPGA Target>New>VI to create a new VI on the FPGA to begin coding.