Okay. I will talk you through how to do a motion path then best for you to fill in the gaps as to what you need.
Create a library movie clip containing your object you want to follow the path.
Place this on the timeline on its own layer, then highlight that layer.
Below this window you should see a rubbish icon. To the left you will see three other icons, select the one in the middle, what looks to be like a + following dots to a box. A guide layer should appear above the the layer with your movieclip.
Draw a simple curvy line on the guide layer with a start and end point, like an S shape. Now select the moveiclip object on frame1 and drag it to the start of your motion guide, the circle in the center of the object should automatically lock onto the start of the motion path.
Then go to frame 15 and insert a keyframe. Now move the movieclip object to the end of the motion guide object and again it should lock into place. (Make sure your guide layer extends to the 15 frames as well).
Then select frame 1 containing your movieclip object and create a motion tween. This should do it.
On the final published swf file the motion path will be invisible, but if you need to hide it while inside flash mx, select the guide layer and below the eye icon choose the dot which will change to a cross and therefore will hide the guide.
Not sure if this is what you mean but hope it helps!