Hello again!
I had done a .skp file now that simulates this really good, I think. So if you cant run the simulation (track/follow) correct, then I don't know what it is. 
It's a very basic model, with two box with name on, Track and Follow. Right below the names there is letters, that is how to move the box right/left. (WASD keys are used)
Here is the file:
TrackFollowTest.skp
/hpnisse
Hello!
The text Camera track NAME should be in the Scene Description.
And if you want both Track and Follow in the same scene, you need to type in.
Camera track NAME. Camera follow NAME
in the Scene Description. (you can have diffrent name on track and follow objects)
I've tested it right now cause I didn't remember, but I got it to work.
Hope you get it to work to.
/hpnisse
Hello!
I installed the SP3.2, it works really good.
And the "Piano-JukeBox7" is awesome, its not slow in frame-rate.
I had seen the Animusic Movies before and think thats great done.
The piano works great, and I add a little stuff to it, when it press the key you the key "lights up" red.
Cause when I see at the cool simulation its a little bit hard to see which key thats playing.
It's done with a simple on/un-touch that you use, and works great. 
Fun that you fixed the bug
Fixed bug where solids would drop into floor first time you run..
It was a bit boring, but now it works great that to.
/hpnisse
Hey!
Thanks for fast answer, is it possible to "getTorque/velocity" to know if something is moving in any direction.
And get the speed of an object, if I will do a speed/RPM -meter?
/hpnisse
Hello CPhilips! (or someone else).
How can I use Velocity & Torque in sketchyphysics 3.1?
Is it something with, get the speed of a physics joint (hinge/motor for example)?
Some examples or something will be appreciate.
Its from this website that you named in this post I find it, but no instructions how to use them.
http://code.google.com/p/sketchyphysics/wiki/ScriptFunctions
/hpnisse
Use JointConnectTool, same that you used before.
Click on the floor and press "CTRL" (Control)[Left], then press the hinge.
Or you can start with the hinge (Ctrl-click) and then the floor, dosn't matter.
/hpnisse
Okay! Sorry
If you want it to follow a object, then
If you don't know how to name objects:
Hope this is what you searching for.
/hpnisse
Hey!
If you dowload SketchyPhysics 3.1 http://sketchyphysics.googlecode.com/files/SetupSketchyPhysics3.1-Sep27.exe that CPhillips released a few days ago at this forum, http://forums.sketchucation.com/viewtopic.php?f=61&t=31262&start=0.
Then you can use this script in an objects script-field:
ontick{
camera.set(camera.eye,transformation.origin,[0,0,1])
}
This will follow the object that you need.
/hpnisse (script is from CPhilips, that created SketchyPhysics 3.1)
No, it was the same thing with SU7, so I think that probably is the computers fault.
I've got the simulation to work with:
Sketchup 8
SketchyPhysics 3 (last version I think)
And it runs on a computer with this:
Processor: Intel Pentium 4 - 3.2GHz
RAM: 2.5GB
OS: Windows 7 Ultimate 32-bit (86-bit)
So the simulation is slow but it works fine. (only slow in big physics models, if the .skp file is over 1MB)
And I had no other (heavy) plugin like Twilight or somthing like that.
/hpnisse
Hehe, thank you.
Have a nice day you too, just fun to help.
There pretty nice weather in Sweden to.
Hello again, first, Yes I have a real name: Tim.
I've downloaded your model and do stuffs that I think you want it to be.
The "Sliding" stuffs had tooo many groups, you don't need that, so just one "Big" group with all small Groups inside. I don't know if the physics simulation can't handle to many groups.
And then I changed the groups that are around the cylinders to "Convexhull", and the cylinder was not in the right direction, so the cylinders where the big problem in your model.
I upload the fixed model, and just say if there is'nt right.
RE_Slider_Problem_02.skp
/Hpnisse (Tim)
I've downloaded the model, and after some time I figured it out.
The sliders had "Max" values that stop the sliders to "slide" on to the cylinders.
I deleted them and it works great. (and if you want to stop the slider at the end of cylinders, just put in a negative value in the "Min" box.)
/hpnisse
Question 1: When you press the Circle Tool there is a number in "Measurement" (that named "Sides" when cylinder tool is selected) box. That is the number of sides the circle will have. Just press how many sides the cylinder should have, before start making the circle.
Question 2: When you start make a circle you the box that named "Sides" before will have the name "Radius", just press in the radius you want. Press Enter. Then use "Push Pull" tool and press on the cirle, and then press how high you want the cylinder.
(then you can make a group)
The other questions is out of my business, cause I don't use "Proper Animation".
/hpnisse
I can use the "@var" and "@@var" insted of "getVar..." and "setVar...", but I can't use the "onTouch{????}" funcion in the "Scripted" field.
But the "@var" is pretty good, its shorter than "getVar".
/hpnisse
Hello.
I made a model of what I think you wanted.
Is it about what you searched?
/hpnisse
Hey.
The ratio is on the first joint, if you press "JCT" (Joint Connector Tool) and press on the motor, and then a hinge. The motor will get the "Ratio" box.
I've created a file with examples. If the motor have the ratio and you write "2.0", then the motor will go twice as fast than the hinge.
The example have four diffrent "motor to hinge" and "hinge to motor" gears.
/hpnisse
Select one of the two joints that you have "gear" between, then open "UI" (skechyphysics inspector)
In one of those joint there are a box named "ratio".
/hpnisse
@unknownuser said:
...Once you've made a single link once for the type of chain you need, you're done. Copy/paste at will.
And if you do the first part to a component, and then copy it, so will it be much easier to change the style of the chain later.
/hpnisse
I think that is the only way if you need to create holes with SketchyPhysics, cause there is nothing what I have found that can handle "concavo" objects, skechyphysics can only handle "convex". I've read that somewhere, I don't know where.
/hpnisse