When adding the player tag to DFP, the following settings need to be applied:
Ad units: select either Custom or HTML.
Selecting a Third-party might cause failure to render the player as the player cannot be loaded through a Third-party iframe
If a macro is auto-detected, it is resolved automatically.
Values sent from the player override detected values.
Tag Options: Serve into SafeFrame: keep unchecked
Select Tag Options: Enable single request: keep unchecked
On the DFP (Ad Manager Side) you can select 1x1 line item
If 1x1 was selected on DFP - on the Player template check DFP 1x1 for the player to target the DFP line item.
Otherwise, select the position selector normally.