Help! Keyframe tweener overshoot

Box8068_31c338ee4b

Hey everybody.
Carrara 6 Pro
I have a weekend of animating planned. It's going to be a rough weekend if I can't figure this out.
Keyframe overshoot is my problem. I thought discrete tweeners would fix my problem but it appears not.
Ok, I'm animating a analog voltmeter.
At zero sec Meter reads zero, all good. At one second I want it to move up to 4 volts by rotating the needle.
So just before one sec I alt drag the first keyframe to " Hold that position this is where I want the needle to start moving.
So far so good. At one second I rotate the needle to 4 volts, so far ok.
Now at 4 seconds I want the needle to rotate back to zero.
So I alt drag the keyframe to just before 4 secs to " HOLD the needle and mark the starting point for it to drop back to zero.
Then I duplicate the first frame at zero so the needle will fall down.
Problem, if I check all keyframes the needle is in the correct place, but when I play the animation I get a huge arc the needle rotates to 10 volts! no matter what tweener. discrete, or liner. It seems to interpolate a cure but I thought liner or discrete tweeners would solve that.
Also I seem to notice small movements I don't want like Carrara is always calculating before and after tweeners, again I hoped discrete tweeners would lock animation to absolute values but that doesn't seem to be the case.
I almost posted this earlier, but when I looked back at my project I thought I had had the wrong tweener, and switching to discrete seemed to fix it., but it has happened again. unless Carrara 6 has a bug that loads the project default tweener and ignores the fact you switched the tweener to discrete. Still I wish I could stop it from precalculating keyframes.
Help!
and tanks
8068

Box8068_31c338ee4b

More Info
It seems the problem is possibly related to the tweeners associated with the keyframes , ALT Drag the keyframes.
If I create a new keyframe as a " Hold Keyframe" helps but I sure wish I could copy and paste keyframes. The ALT Drag method
seems to create some of the problems.
Thanks
B

WendyLuvsCatz

is it just in playback or in render?
preview playback is jerky and innaccurate at best.
I also make sure I manually create keyframes at each point because only the new rotations and transforms get keyframed
this is vital dollying and panning cameras for example.
ie if you rotate on the x-axis at 20sec then the y-axis at 30secs it tweens from the 20sec keyframe for the x-axis movement so clicking add keyframe creates triangles for ALL the transforms, rotations, scale etc at that point!! so the all next ones will be calculated from there not some a previous point.