Hi,
thanks for your question, and sorry for the trouble.
Yes, this sounds like an easy fix, but unfortunately, it isn’t 🙁 The external PHP library that TablePress uses to parse formulas basically goes through the formulas one character at a time, on the look for operators, function names, numbers, etc. That detection can however not take into account operators that are more than one character, from what I know.
I’d definitely like to add support for this in the future, but for now I can only suggest to rewrite such expressions from
a <= b
to the equivalent
NOT( a > b )
or to do all the formula stuff in e.g. Excel and just import a CSV file with the calculated results into TablePress.
Regards,
Tobias