Thank you Thomas for the precisions.
BitD I have learnt the hard way, with a lot of frustration, that the 1.3 Shell was not able to 'expand' the "$<variable_name>" but in the other hand I always found strange that the 'Execute' command that is used to launch a script didn't implement such a parser.
Fortunately, BitD
ARP for 1.3 addressed some of the 1.3 youth errors.