Great, if PAUSE works that is a good first step.
For dynamic waiting inside iframes, we recommend to use local computer vision with visualAssert | ImageOfSomethingInFrame.png. This command will check every second if the image has been found. If not, it waits until the ${!timeout_wait} time has been reached.
If you prefer to wait for an image to disappear, that is also possible but a bit more complicated.