Hi, I have big problem with rb333. I have had a rc1 firmware and try upgrade to rc4, so I’m uploaded the firmware to mt and rebooted the system. And… the blue led is shining, and i hear ONE beep. and noone after it. when i connect through the any lan port, Its reconect every one second. Didn’t have serial cable ;/
Make serial cable it and didn’t have in next time problem!
http://www.mikrotik.com/testdocs/ros/2.9/system/serial.php
Router Side cSignal Direction Side (DB9f)
1, 6 CD, DSR IN 4
2 RxD IN 3
3 TxD OUT 2
4 DTR OUT 1, 6
5 GND - 5
7 RTS OUT 8
8 CTS IN 7
if you dint have (DB9f)
get from old cable modem or somthing like that 
what method did you use to connect - through winbox? telnet?
I bought mine serial cable from ebay similar to this for $3.
http://cgi.ebay.com/NULL-MODEM-SERIAL-UPDATE-CABLE-DB9-RS232-PANSAT-FTA-nn_W0QQitemZ150156011389QQihZ005QQcategoryZ67879QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
We have same problem.
When we upload package to rb it shows in files list , file type “file” ( should be “package” ).
And then after reboot rb is out of service.
Only netinstall helps. After netinstall another upgrade from winbox is ok.
Strange. 
Czechu