Starting today, a first public beta of StitchBuddy 3.4.3 (2961) can be installed via TestFlight using this link. This version is solely addressing one issue when a shape's control point, equal to an anchor point, was dragged: Due to the identical point coordinates a division by zero was performed, crashing an internal Apple function when drawing the shape.
With this limited scope I'll keep the beta testing phase short, but it hopefully confirms the fix is working in your environments.
Although I didn't realize any major issue, this version is still a beta release: Feel free to test and provide any feedback in this discussion.