Only 1 global mbox is supported across your account. You can limit where your activities run by adding URL rules to your activities: https://marketing.adobe.com/resources/help/en_US/target/target/t_temtest.html
You could also pass a parameter on the page using targetPageParams() (https://marketing.adobe.com/resources/help/en_US/target/ov2/r_target-atjs-targetpageparams .html) and then select those parameters in that "configure URL" section in the Visual Experience Composer, or by adding the parameters as "refinements" in the form based composer.
Hope that helps!
Group Product Manager, Adobe Target
I see that targetPageParams() sits under at.js documentation. Can it also be used with the mbox.js script?
If not, is the alternative mboxUpdate(), using the global mbox name?
Oh interesting, it's not actually specific to at.js. Looks like we have it documented in 2 places. You can use it with an mbox.js implementation. Here is the more generic documentation for targetPageParams(): https://marketing.adobe.com/resources/help/en_US/target/ov/c_pass_parameters_to_global_mbo x.html