Progress bar for .rev download

When clicking Export->For backup (.rev), nothing happens for a long time. It looks like there is an unreported error. Then suddenly after a while, a save file box (windows) pops up. I guess the reason this happens is that my file is quite big and the the server is too far away (I'm in Vietnam). This causes a big delay from user input to screen feedback. There should be a progress bar or at least some message like "please wait" while waiting for the file to become available.