Have a look at https://github.com/helmlingp/WS1UEM_CustomKiosk/blob/main/ExampleKioskProfile_with_CitrixWorkspaceAp... example.
on Edge browser blocking ICA files, I guess you would deploy the Browser CSP - https://learn.microsoft.com/en-us/windows/client-management/mdm/policy-csp-browser but not sure as I've not done that
