Firstly, get your image, i am using this globe

Open Image Ready:

Open the file in Imageready, by either dragging and dropping it into the app, or by opening it. The file should open with multiple animation frames and layers(this doesn't happen in PS, it just opens the first frame).

Next, select all the frames using shift + clicking the last frame while the first one is currently selected.

After that, go file>export>animation frames as files.
Export them to a set folder, then open all of them into Photoshop.
Now, using the filename, in order, copy paste each one into the userbar psd, don't touch them till you have copied them all, in this case 18 images. so you should have 18, perfectly aligned layers.
next, select all the Earth layers (group them if you want for ease) and free transform the layers. What you can do is select all the layers, but keep only one visible, all will transform, but you will have a clear view of just one so you can transform easily

Next, make your userbar how you like it. What i did was add some stars in the bg, using the noise filter trick. And then i added the moon and sun and a nebula in the background.
(Obviously it's no to scale, the sun is much bigger, but it's a userbar, work around it)now all that's left is taking it over to Imageready, and using the same or a different timing that was used in the original gif. And that's it. I used a different timing since it was too saft, i slowed it down by .02 of a second to make it a bit mroe realistic.

Remember, the size of a ub, depends on not only the number of frames, but what's being animated. If you have a large picture, say the whole bg moving, it's a huge pic. If you have a small picture moving with a constant bg, it will be saved with a lower size since less colors are needed to be remembered.
Also, remember not to use a lot of transitional images, like gradient that take too long to change, that spoils the look since the gif can only remember 256 pics and it's hard with so many shades