I have to give up to find the error myself. It is not the wave motion gun and the error occurs not with 100% reproducability. It seems (!!!) to be connected to the order the components are destroyed and occurs more frequently if components with high damage resistance are present. But this is just my impression and not sure at all.
Whatever has caused the RCE according to the quick reply from MM the next patch should fix it! And more good news: this next patch should be released next week .