Motion Tween (CS4) - please help

Question

I'm a student trying to finish (what should be) a pretty
simple assignment. I'm creating a 30 second banner. From frame 1 to
frame 90 (3 seconds), I have an image (movie clip) sliding in and
"bouncing" into place with a motion tween (used the motion editor
to get the "bounce in" ease effect on the tween). So, currently,
after frame 90 there are no more frames on that layer; my image
disappears.
Now I want the symbol instance to stay in place for the next
x frames, while stuff on other layers slides in on "top" of it. But
if I go out to frame x, select it, and hit F5, F6, or F7, it makes
the symbol stay in place over those frames like I want, BUT it
screws up my motion tween. I lose the "bounce in" ease, for some
reason. How can I get my motion tween to work like I want from
frame 1 to frame 90, and then have the symbol instance stay put for
the next x frames after that?
Thanks!
Christophe

Answer 1

My instructor said just to go to the frame in the layer, go
to frame x and select it, then do insert>timeline>frames. But
that still screwed up my tween. The object slides into place, but
the "bounce in" ease is no longer visible.
I found this workaround - which doesn't seem very efficient,
but it worked. My motion tween ends at frame 90:
1) select frame 91, hit F7 to insert a blank keyframe.
2) go to and select frame 90, select the object on the stage,
copy it.
3) go to and select frame 91, paste in place.
4) Now go out to frame X, select it, and hit F5. Object now
sits in place from frame 91 to frame X, and "bounce in" ease of the
motion tween from frame 1 to frame 90 isn't affected.