Thanks for pushing for higher LabVIEW editor and run-time stability. Around two years ago I too was bitten by an issue whereby my LabVIEW 2018 application wouldn't build into an EXE anymore after using my own custom-made malleable VIs deeply nested as subVIs inside other lvlib-owned VIs. The code worked perfectly fine in development environment. There were no broken run arrows. For a while I played tickbox roulette exactly as you described. In the end I refactored the malleable VIs into regular VIs. This worked, but it led to code duplication in the sense that for each malleable VI I had to create two or more regular VIs that were virtually identical, but were adapted to a particular data type. The whole investigation and refactoring cost around a week of work.
