Help with ECS controller

[jo-jo]

Can any one help! I am writing a file for an ECS controller that calls sub programs using a numeric value entered into the variable Rxx eg R1, the sub program file names will be a six or eight digit numeric.
The ECS programming instruction manual I have states that it should be possible using the R type variables.
I have entered the value into the variable R1=123456, and then used the syntax L<&R1> or L<R1> to call sub routine 123456. The syntax is dependent on which version of the controller and I am not sure of the controller version.
I cannot get it to work, one returns a syntax error and the other thinks R1 is the sub routine file name.
Have contacted the machine manufacturer and ECS without reply.