I have a dashboard that I export as an image to certain locations but what I see happening every now and then is that the object won't resize itself to fit the content and I'll then get scrollbars and cut off data appearing on the images.
Is there something I can set that will allow these objects to resize automatically?
I don't think objects can resize upwards (i.e. get bigger) automatically but they can get smaller. Try switchin to design mode, increasing the width of the object a lot and ensureing Size to Data is checked in the Layout tab of the object properties.