Hi Ruth
I came to this community page because I also broke the parser!
Your help with other enquiries made me realise I must have made a syntax error. Because I'm a complete novice this is hardly surprising, but would you be willing to share your method for working errors? What do you check first and next etc. I have just started using the Survey123 connect form and don't know anything about programming; I'm used to excel telling me when I've omitted a critical character eg a parenthesis so will probably make a lot of errors there, but for example if I could break the parser with just an overlong field name then that would be the first thing to check? I haven't looked to see whether there's a syntax checking scratchpad website (as I've found for html, where they show you what the formatting will look like for the input html coding, and vice versa - I've found that a handy way to learn what works).
I have been to the survey 123 troubleshooter which was useful in a way but didn't help me step through my form to diagnose my problem, whereas your solutions helped me think of the basic errors I could have made.
So for me in the end it turned out that it wasn't my long RELEVANT formula that was breaking the system, it was simply because I'd put one RELEVANT formula in same row as the field it referred to, instead of the row for the field that depended on its value.
Not an urgent query, as I've now solved my problem, but all tips gratefully received.
Thank you
rachel