Transition options are not available in Craft plugin for Sketch. I've tried updating and uninstalling / re-installing Craft Manager and the plugin, and I've also updated Sketch. And yes, I've tried turning my mac off and on again.
* Sketch 57.1
* Craft Manager 1.0.87
* Craft plugin 1.0.59 with Prototype 2.3.141
Here's a screenshot of my prototype panel in Sketch: