I installed the FW 0.4 on my babyjet. Upgrade procedure was painless, really.
Findings:
-I still only have 3 working dies

-BFGMiner works like before
-CGMiner doesn't find a device anymore (tried 3.11, 3.12.3 and 4.0 w/ zadig)
Hashrate seems actually a bit lower than 0.2. Might try that 0.3 release tomorrow.
From what I've read, FW 0.4 doesn't play nice with HW 1.1, so I haven't upgraded. The latest CGminer git has the HFA-FAIL-DROP. I compiled it this morning. CGminer says it is on the wrong USB ID/Vendor and can't get a name. The BabyJet doesn't even click on/off when CGminer starts up.
Here are the lines from the debug file...
HFA: Failed to receive OP_NAME response[11;21H3[11;64H1d6b:000[13;21H3] RES: Hashfast (6:10) lock=0[K
HFA looking for HFA 297c:0001 but found 1d6b:0001 instead[22;1H[K[23;24HNo devices detected