AgfaPhoto DC-600uw

An odd problem here. With my Olympus OM-D E-M1 and FL-600R Flash (both new), I am trying to set the Mode on the flash to "TTL-A", however the TTL-A setting does no appear as one of the modes. After some experimentation, I found that if I mounted the flash unit - but did NOT lock the hot shoe - the flash displayed the Ttl-a setting. However, as soon as I flipped the lever to the right into the "locked" position (about 2/3's of the way) the Ttl-a setting disappears as a mode setting. The flash...