> "But it seems I have to make a border for every frame, because it won't let me change the other frame borders."
Actually you don't need to...
Create a Empty Layer, move it so it's on top of all the other Layers in the Layers Pallet OK enough babble about that...
If you had the top Layer selected then when you created the new Layer it should be place on top, since any new Layer is placed directly on top of the Layer that is currently selected.
Select the first Frame
in the Animation Pallet
Why ? - Because in Photoshop and ImageReady when you change something in a frame all the frames after it will be affected. So if you have a 5 frame animation and change the Visibility of some Layer (via the eye thing next to the layer name) in the 3rd Frame, the Visibility of that Layer in frames 4th and 5th will also change, while the visibility in frames 1 and 2 will remain unaltered.
When it comes to layers the rule is always: the visibility of any Layer has priority over the visibility of the layers bellow it.
Anyway... with your first Frame and the Empty Layer selected click on the eye thing next to the layer several times (2 times) to make sure it will be the same in the rest of the Layers, after your finished the layer should have visibility On if they dont, then you clicked more then two times you dumbass ... so just click one more time to make it visible
Now Select All then a Stroke and you should have a simple border for all your frames
Above I mentioned some steps that are pretty much useless, but you should be able to understand the process better that way
that and I had no idea what you were doing wrong