OP co-author here. It could be worth a shot to try (I'll do when time permits). However, I am doubting it would help given how often LibreOffice was freezing

OP co-author here. It could be worth a shot to try (I'll do when time permits). However, I am doubting it would help given how often LibreOffice was freezing with it (without crashing). My suspicion is that the formula recalculation is triggering more often that it should, and I could not find any way to prevent it. Excel provides options for manual triggers; if Calc does too, that might just solve the problem. PS: I am not deeply familiar with LibreOffice. :-)