Thanks Michael - I tried all the shut down /turn off - turn on measures a number of times. It seemed to randomly respond in the end and now it’s back. I’m finding my copy of Vectorworks very clitchy at the moment - I have a new issue with inability to drag layer order for some reason, again frustrating but easier to work around for the short term at least. I have just done a software update so it is all up to date, maybe due to the update itself?!