The executable model is not able to parse a binding to a variable like the DRL model.
A rule like this will fail compiling in the executable model while it will not in the old model:
rule "Rule that breaks ExecutableModel"
@filename("rules.drl")
ruleflow-group "RFG-1"
salience 5
when
$values: List()
$cwv: ClassWithValue( $value: value.charAt(5) == '5' )
then
$values.add($value);
end