Using Captivate 2017 I can create a custom navigation bar (almost) but it doesn't work.

I'm trying to create a custom navigation bar with various buttons including TOC, back, next, CC, Options, Mute, Play/Pause, etc.

I add a smart shape, select use as button, apply images for up, rollover, and down to their respective states, and set the object to display to end of project. The action I select is irrelevant for this problem.

This works if I have up to 3 buttons, then if I have a 4th or 5th button, when I preview it, the displayed project goes completely white. I get the same results whether I use graphic images or text only, whether I use square or rounded cornered objects, whether the object is on a normal slide or a master slide.

Adobe Captivate 2017 Release 10.0.0.192