This is very late, but I have the same setup as you and the flash manual does not mention the 7D. I think it was printed before the model. Thus it makes it very confusing. I get the same results as you. Auto never shows. It must be for older models. I get great results shooting thru a 32" silver/white umbrella, to knock out the strong shadows using wireless, and the onboard flash. And, with the 1:2 ratio control also. I keep the asa at 100. I am very happy with the camera and the flash. I use Photshop CS2 and shoot in RAW + fine mode in Adobe-rgb. Then I use the Adobe raw converter in Photshop to get 12 bit per color sensor data. I then use the auto convert mostly, and save the file to tiff after the adjustments. That eliminates the jpeg compression problems, but takes more hard drive space. My H-P printer has an Adobe-rgb profile and that is my working profile in Photoshop. I need to get another 5600 or 3600 for two flashes. Still trying to learn what all the modes and control stuff is really doing. Cheers.
JIm
MAXXUM 7D,VC-7D, 17-35MM F2.8-4(d), 28-75MM F2.8 (d), 5600HS(D) Maxxum 4000af flash (non-wireless)