You can change the precision with which floating point values are output by using the precision environment declaration. For example:
precision 3
float Max is 23.0
disabled key DisplayMax at position 30 40
text Max
will produce the following text in the disabled key DisplayMax:
23.000
If no precision is specified, the default value of 2 is used (which truncates the value after two digits to the right of the decimal point). If a precision of 0 is specified, the decimal point will be displayed, with no digits to its right.