Hi there,
Retina creative can be setup as follows:
- Create necessary campaign and target to your 320x50 ad unit
- Upload your retina creative as an Image creative
- Save and pause this creative
- Right click on the paused creative and copy the image URL
- Add a new creative for 320x50 and set to HTML
- Drop in the following tag into the HTML section:
<a href="CLICK URL HERE" target="_blank"> <img src="PASTE IMAGE URL HERE" width=100%> </a>
Best,
Wyatt