Dear Plasmaticon!
Thank you for choosing National Instruments!
Addressing your issue of disabling controls depending on certain conditions, there is, unfortunately no function to do this.
However, there is a powerful feature in LabVIEW which is pretty straight forward to use - called Property nodes. You can create a property node for each control on the front panel by right clicking on the control and selecting Create > Property node. You can also then manipulate the front panel control by means of this property node - including enabling and disabling the control at will depending on when certain conditons are met.
We hope this helps.
Thanks and Regards
ShekharS
National Instruments.