I've made the following object dynamic without a hitch...until I attempt the WebSetResponsive. Are you allowing for this?

        Object oLogo is a cWebImage 
            Set piColumnSpan to 6
            Set psUrl to "images/hs_Logo.png"
            Set pePosition to wiFit
            Set piColumnIndex to 1
            Set piHeight to 160
            WebSetResponsive piHeight rmMobile to 100  // Best for small smart phones