So here is how I think you could proceed:

• the setvar command allows you to store variables
• these can be (under the control of the replace command) substituted in other commands using the #(var) syntax
• you can source a central file using the cfg command
• this file includes your setvar settings

In your update script you would have something like

mod cmd UP0 prot http://192.168.0.10/firm/#(firm)/ 

Does that fit your requirements?

The update script syntax is ugly but quite powerful

Best Regards, Christoph