[Brian Jones]

not that I know of, the metaball, no matter how many parts it has, is one generated object. The usual proximal methods of differing color on the metaball use either the proximal as a layer mask or in the alpha channel to show alternate colors in the same material.
The proximal can’t transfer color from another object it only produces a black to white gradient based on the proximity of objects (or object elements).

[Brian Jones]

the texture tag can be animated. Texture Tag/Tag/Material shows and controls which material is actually being used by the texture tag. Keyframe it and it will fade from one material to another over how may frames you give it.
That’s a lot of texture tags by the sound of it though so I don’t know if that’s a good solution for you.

[Brian Jones]

do the poly selections for all the objects disappear at the same time or will it be staggered timing?

[Brian Jones]

your curtains don’t look like they are touching the floor. If you have dropped them lower and they don’t deform the same way, have you subdivided the extrude (the curtains) as much as in the tutorial?

[Brian Jones]

are the gears going to touch each other (so some are going to be going clockwise and some counter-clockwise?)
Folder?

[Brian Jones]

lots of advice out there, do a search here for ‘wormhole’. If that’s not the sort of thing you’re after more details would be necessary (for me anyway)

[Brian Jones]

the deformer’s order is very important, if you have the bend as the first child of the object and the spline wrap as the second child, when you adjust the bend it should do what you want.

[Brian Jones]

You can use a Cloner (not the best way probably but just saying…) by putting all the objects into the cloner (Clones set to Iterate – which is the default) and setting the cloner Mode to Linear (or using a spline (cloner in Object mode or Linear with Spline Effector)) to arrange the text out) – spacing is the problem here (the cloner will control the spacing of the letters and it’s kind of a pain (but possible) to get the letters exactly where you want them) but the MultiShader set to Index Ratio works like you’d expect.
Putting all the letters in a Fracture object is better for spacing (they stay exactly where you put them) but Index Ratio to control the colours can be a bit of a problem. It works well if you use a Step Effector (with Color Mode set to On) with the Fracture, then use the MultiShader set to Color Brightness.

10210_multishadertest.c4d.zip

[Brian Jones]

depending on how detailed your tumbleweed is (geometry or texture based) you might want to use a simple thing like in the example file (but fitted to your tumbleweed) as a proxy for quicker calculation. Here is a simple test with a Wind object pushing a “tumbleweed” with enough friction in the ground and tumbler to make it roll instead of slide and with Rotational Mass set low enough it can do that easily.

10187_tumbleweedtrial.c4d.zip

this is what I mean by proxy

10188_tumbleweedtrial2.c4d.zip

[Brian Jones]

what version of C4D do you have (and what package)? It’s very possible with Dynamics but it’s also possible with xpresso