Build 181 solved the CW breakup by pausing a couple seconds before sending the first character. This fix applies to the transmitting station only. If you are listening to a station who is not using build 181, you will still hear the breakup because he begins sending without enough pause for the connection to stablize. Some stations always have breakup problems.
I was having CW qso with Rich at that time with build 181 both sides. Both heard breakup each other so we started couple of v's at the beginning of TX to remove the breakup. We hope you check it again.