Have you tried google? 12.4 million hits for "jews against zionism". I cba to paste a load of links though. There are fucking loads of jews and jewish groups against both zionism in principle and against the actions of the current israeli state. Come to any palestine protest and you will find us there.
I'm just going to post up a single link, a group called "Peace Now"
http://peacenow.org.il/eng/
not against zionism, but against the way that the Israeli state treats Palestine/Palestinians. They are Israeli Jews btw in case you don't care to check through to the link. Is this enough material evidence for you to answer this: "the assertion that Israel does not represent general Jewish sentiment can be easily disproven by presenting evidence of material Jewish sentiment condemming Israeli atrocity."?
Honestly, I find it hard to believe that you are (a) either completely unaware of the substantial jewish criticisms of Israel or (b) couldn't be bothered with a simple google search, so I'm wondering what your agenda is here?