I just ran it with Active Home, i have Version 1.4 (B2.0.70) and it works correctly.
Im running it with my homemade program and I'm getting the 0xA5 and i stop it with the 0x9b. I then waited a few seconds and then sent 0x04, 0x66. After recieving a check sum of 6A, i sent the 0x00. i didnt get anything back. I moved past it like you mentioned and went on to send the 0x06, 0x62 and im using the XPS3 Fluorescent wall switch (WS13A) im not getting a response out of it. I made a program to show the input/output...
Byre Received at 5:34:43 PM : 498 msec: A5
Byre Received at 5:34:45 PM : 339 msec: A5
Byre Received at 5:34:47 PM : 181 msec: A5
Sent at 5:34:48 PM : 668 msec: 9b
Sent at 5:35:44 PM : 934 msec: 0466
Byre Received at 5:35:45 PM : 43 msec: 6A
Sent at 5:36:04 PM : 199 msec: 00
Sent at 5:36:32 PM : 206 msec: 0662
Byre Received at 5:36:32 PM : 314 msec: 68
Sent at 5:36:36 PM : 285 msec: 00