Yes, you need a subworld.
Here are some simple steps:
Make an Empty object and place it at the object center of your moving object (say a cart). Now... the point is to get the empty to move with the cart... there are two ways to do this: Make it so that you can move the subworld and move the cart together (parenting) or just animating the subworld with its own anim.
Now, I had horrible trouble with the latter option when I was trying out subworlds--it would keep sliding out from under me because it's hard to get anims to match perfectly (so it was like I had greased the deck on my ship "the Cube.001"

ok, it was tramatic when you'd slip off).
So I suggest you parent your subworld empty to your cart (and delete the current anim for the cart and give that to the subworld). So, select the cart (or whatever you have) and then select the empty (subworld) and press CTRL+P in object mode.
I won't go into too much detail about the IPOs and unhooking them from the object because I assume you kinda know what I'm talking about.
Ok, now try grabbing your subworld... your cart should move as well. Now animate the subworld or switch the empty to use the cart's IPO and delete the link to the cart (what I was talking above).
Now that you have your cart following your empty you can start the fun stuff (err fun for me at least

).
Give your subworld the alcscript properties (just add this to your current alcscript stuff if you already have stuff set for this object):
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<object>:
type: subworld
Ok, now make the entrance-region:
Add an object (say cylinder in this case for your spinning thing), place it where you want to be under the influence of your subworld and add this script:
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<object>:
type: region
regiontype: subworld
region:
subworld: <subworld-object name>
Ok, now make the objects you want to collide with when you are in the subworld have this script:
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<object>:
physical:
subworld: <subworld-object name>
Remember that the objects are not colliders in the regular world if you make them colliders for the subworld.
Now you need an exit region... try looking over the different ways you can do this in the wiki (that part's pretty clear).
Oh, and there are enter and exit regions... they're like doors in and out of the subworld (so exiting the entrance region won't help you after you've entered the region).
If you have questions just ask.

Currently getting some ink on my hands over at the Guild Of Ink-Makers (PyPRP2).