Have you considered creating a button with a custom copy command that would do all this automatically? For example I have a button set up with the following command:
When copying from source to destination it skips identical files and copies only brand new or changed files without any prompts. If you want prompts, and I would suggest enabling them at first until you know it's doing what you want, then change the command to:
Wow. Thanks for the response. I'd set up custom buttons to do file compares way back, and then apparently completely forgot about the fact that you can do that kind of stuff in Dopus.
I still think the prompting could use a little work, but it's nice to be reminded of that option.