wpDiscuz Widget Plugin causes error 500

wpDiscuz Widget Plugin causes error 500 and thereby generates various error/warning messages from jetpack and google and also messes up the CSS code by showing random pages as if it was in cellphone mode. When i disable the plugin it works perfectly. I have removed all custom CSS and tried to disable all other plugins but same issue. I also tried to reset all wpDiscuz settings including the wpDiscuz widget plugin. I also tried to change all the settings one by one inside the wpdiscuz widget plugin but still get the issue.