May I retrieve a copy of a European patent application for placement in a US application if priority to that European patent application is not claimed in the US application (for example, if the EPO application is cited as relevant prior art)?

 No.   A copy of a European patent application (i.e., priority document) can only be retrieved under this program if the US application into which the priority document will be placed claims priority to that European patent application.

16.Will the copy of the priority document retrieved from the EPO be certified?

The requirement under 37 CFR 1.55 for the certified copy of the foreign application will be considered satisfied if applicant files a request in compliance with 37 CFR 1.55(d). 

USPTO FAQ - Questions and Answers (12FEB2007)