ZynAddSubFX won't open GUI in rc7

This just happened to me yesterday, It started when I opened a project and tried opening one of the Zyn synths in the project. LMMS froze up for a few seconds before unfreezing and not letting me play notes in the piano-roll in LMMS. However, once I clicked the "Show GUI" button again, it let me play the synth, but it had reset itself.
Now it's doing this whenever I try opening any instance of Zyn in LMMS.

The report names no source files, tests, or entry points. Start by reproducing the problem when opening any Zyn instance and observe the freeze, piano-roll input, GUI reopening, and synth reset; done means Zyn opens normally without disrupting note input or resetting.

Written by the indexing model from the issue text.