I have lost a lot of hours with CCS's driver for AD7705 (V 3.227, 2005).
I think there are 2 errors (of course, I verified with Analog device data-sheets).
1: Inversion of the sign of signal DRDY
2 ...
In debug, you click "debug config", "ICD program" button (the 4th) (or lauch ICD.EXE?)
Then, in ICD control program (I have V 2.6), you click on "advanced...":
"Erase mode" / "Bulk erase on write" i ...