CitationJet 525 with TDS Garmin GTNXi 750

[mldavis2]

Using version 1.0.3 of the CitationJet 525.  I have used this Garmin add-on in other aircraft successfully, but the CitationJet autopilot will not couple with the Garmin GTNXi 750.  I have tried everything I can think of.  Flight plan is activated in the Garmin, GPS is active in the Garmin, the standby gyro is active in the CitationJet, NAV and autopilot are ON, the GTNXi 750 is chosen in the EFB and is the primary choice in the TDS menu.  I've seen a video of this being used in the CitationJet, so I know it can work.  What am I missing???