There are some compatibility issues with IE10. You need to be in IE10's "compatibility mode" (emulate IE9) in order to browse and upload media and to insert line breaks in the editor. A small inconvenience that I hope the JoomlaCK folks will fix soon.
Thank you for the review. Just to let you know that the latest release (JCK Suite 6.1) now comes with support for IE10 (standard mode).