I have just come across this issue when updating from 18.4.26.12 to 19.7.15.12.
Like the OP in https://www.nevron.com/Forum/12739/When-is-it-adviceable-to-call-NevronChart100ocumentCalculate-and-RecalcLayout I started getting numerous problems where no chart data was drawn in the newer version.

I also eventually tracked down that removing the Calculate resulted in the chart reappearing again.
I wasted considerable time tracking this down. It would have been good if some mention of this was made in release notes (or did I miss it?).

This is clearly a bug here that needs fixing.