I was getting the "ZlibHex unkown subencoding 49 encountered" errors as well, but if you edit the profile you're using to connect, and turn off ZRLE encoding, maybe that will remedy the problem. It did for me anyway.

I wouldn't have bothered trying to figure this out, but this does seem like the most responsive and "nice" VNC client out of the 3 or 4 that I tried. The fact that it's open source gives me confidence in its future as well.