To select a single keyframe on a flash (CS4) timeline just hold down the cmd button and click. You can then ctrl or right click and do what you need to do. You can also now drag that single key frame to a new place on the timeline and all the positions, rotations, alpha etc for that one keyframe will move together.
If you have more that one keyframe to move you can hold down the cmd and then drag the cursor over the required frames.