if somehow your DataTypeDefinitions become corrupt, uSync will no longer throw a YSOD, it will log it's error in the log file and carry on.
When moving DocumentTypes between versions the first import didn't maintain the "allowed child nodes" - it does now
Known Issues
First save of a DocumentType after setting 'Allowed Child Nodes' (or 'Allow at root' on v6) isn't saved to the uSync def file. this is an umbraco bug (http://issues.umbraco.org/issue/U4-547) the next save of the DocumentType picks this up.
v6 still only works on 6.0.0 & 6.0.3(Nightly builds)
uSync: Release Notes 1.1.1
Some Bug Fixes.
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