unexpected user error (rule_DomainMinMax.minOfDomain ?)

[ott2]

I have a simple spec which:

• works fine unparameterised
• breaks if changing one letting to a given, and providing that in a param file: conjure: user error (rule_DomainMinMax.minOfDomain ?)
• breaks on a 2020-vintage conjure in the latter case with This should never happen, sorry!... IO Error rule_DomainMinMax.minOfDomain ?

Here are the files, with .txt endings due to github's faulty semantics for filenames.

test0.essence test.essence test.param