Selective redirection to external proxy http_mapped

[jb_uk]

We have a requirement to transparently redirect Guest traffic to a Cloud-based proxy. I have been trying to achieve this via the http_mapped service on R80.20. However, despite the access policy rule stating a particular source zone and network, the Check Point is redirecting all HTTP traffic to the proxy. Is what I'm trying to do actually possible? If so, where might I be going wrong?

Thanks for looking!

[PhoneBoy]

There isn't a ton of documentation about the http_mapped service.
That said there are a couple of TAC cases about issues with this service in R80.x.
It may be worth opening a case.