@Joanna Waligora are you still having issues with this? Can you accept best answer or provide your own solution?
The QV support team is currently investigating this problem. I will provide an update / closure once I receive their feedback.
Also, I want to correct my initial statement - max, and length functions work fine, but reverse, instr, and regexp_extract don't.
This problem has been resolved. Errors were caused by QV syntax peculiarities. Details can be viewed in the QV Community post here.
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