Problem with CRMScript iframe

Hello everyone,

in our new project we need a website as an iframe in SuperOffice which should consume some additional parameters.
We created it using CRMScript (... setVariable("url", "https://ourapp?newparam=xxx")). Works well except for one thing.
We need SOClientCrossMessaging calls from this iframe and it doesn't work. If we set the url directly in the GUI Web panel, it works fine.

We don't get any errors in browser console during function calls. It just doesn't work.
Does anyone have experience with ClientCrossMessaging from CRMScript iframe?

Thanks in advance!

Best regards,
Andrey