wiebe@CARYA wrote:
Big question is if it allows you to specify the nr. of decimal points...
Not directly, but it does have the flexibility of working with "subJSON", including using a "<JSON>" tag on cluster items to identify some strings as already JSON, as shown here:

BTW, the problems the OP is having is because the manufacturer is clearly NOT using a JSON library, and is just hacking and parsing raw strings. Thus the obvious bugs like not recognising 22 as being the same as 22.0. This loses the big value of having a common well-specified format, which is to not waste time on stuff like this.