When the gauge contains a scale which is interactive (IsInteractive property is true) and when the Gauge control it is embed inside the RadFluidContentControl.LargeContent then it throws an exception. ComException with Message: UCEERR_RENDERTHREADFAILURE. This is reproducible also: - In any control that uses animation transitions to change its content. - If many instances of a gauge control are added in the transition's control content.
The fix will be available in the R1 2018 SP2 Release.