Can't enter Vex autonomous mode when using MPLab

[Redneck]

So my team competed at a Vex scrimmage this past weekend, and we ran into a problem -
Our robot never goes into autonomous mode on the field! Every other team there got it running, but not us. I found it's at least partially due to the fact that we did our coding in MPLab, while everyone else was using EasyC.

We downloaded master firmware v. 7, and used the latest MPLab template from here

Everything works fine with user control, but the robot never goes into autonomous mode.
We tried changing the Library files, with these results:
Vex_alltimers.lib - Runs autonomous only, no user control.
Vex_alltimers_auton_test.lib - Runs user control, goes in and out of autonomous via channel 5 button on the controller.
Vex_alltimers_wauton.lib - Runs user control only, no auton
Vex_alltimers_wauton_impr.lib - Runs user control only, no auton

The only ones actually tested on the field were wauton and wauton_impr. The team refused to take the chance of having no user control or having auton on a trigger, so we only tried the others during testing in the pits between matches.

We also tried the equivalent Vex_library*.lib files, with identical results.

Has anyone else encountered this problem and/or found a solution?