Can you put the images in the UDV instead? I’m not sure what you want to accomplish, but if you use the same image multiple times, you can add the entire image to the UDV.
I just found out today about placing images in UDVs (there's a post about it on Colum's site) but I'm thinking in more general terms about the placement of UDVs in attributes, and that goes beyond just images.
Let's say I have a UDV that I want to place in the title attribute of a hyperlink, so as to provide a little more info on mouseover – I can't seem to do that right now. If anyone has a workaround for this apparent limitation, I'd be glad to hear it.
This is not possible. And I don’t have a workaround for that at this moment.
You may want to request this as a feature for new versions: https://www.adobe.com/cfusion/mmform/index.cfm?name=wishform