Can't impersonate functionalities in embedded custom page.

Summary:

We have enable the proxies feature in our environment and it seems that it can't impersonate the functionalities in the embedded custom page. We have impersonate a user and created a record. The record created has the Created By value of the proxies' email address not the user being impersonated. Since the proxy feature is enabled, we anticipate that the functions and data that are displayed on the embedded custom page by the proxies will be determined by the roles and access of the impersonated user, not by the proxies.

We would also like additional information regarding this feature; it would be greatly appreciated if you could provide us documents.