try Disabling the preview, it is prbably a conflict with the preview engine and IE 11
go to WebAssist -> Preferences. in the preferences section select the option to disable the preview. you will still have access to the preview by clicking the placeholder to open the preview in the browser.
In newer version of Data Bridge and eCart we are trying to work around this by adding different preview engine options. AIf you upgrade to the newer extensions, you will an option to change the preview engine.