Am thinking about offering a wood deck cleaning/stripping/sealing service as Spring approaches.
Does anyone have any experience in using a Cimex or OP (I have both) as part of this process? Deck sanding is sometimes involved, but this seems to be the only thing I can find anything online about. I thought my Challenger T & G brush might be useful, and Clark at Orbitec tells me he has a brush attachment for my CX20 that should work. My main concern is possibly causing harm to the wood surface.

A CRB type machine would do an excellent job, but OP would leave swirl marks. I do my own using the GLS

My next question would be can a Cimex be used to sand, or screen sand, indoor wood floors, or are swirl marks still an issue? I would think if the weighted version of the Cimex could grind and polish marble floors with creating swirls, why would this occur with wood?

Marble is Hard, Wood is soft, Carpet is softer and it leaves swirl marks that have to be raked out, something you can't do on wood.

Having a deck of my own, with a 2-year old coating of semi-transparent stain, I decided to do my own R & D. With my Challenger, a white pad, and a 60-grit sanding screen, I worked on one area of my deck. I got down to bare wood pretty quickly in some limited areas, but this wasn't good enough.
Next I applied a deck stripping product, and used my Challenger and a FiberMax pad to scrub it in. This showed an improvement, but stain was still visibly in some areas. Next, in this same area, I used my steam vapor machine, with a brush attachment, and blasted away at the remaining stain, which all came out pretty easily. But this was hand work, and given the size of the deck, pretty slow and definitely tiring. Next I went to a new area of the deck, and put down some stripper, just pouring it down here and there. Then I put my T & G brush on my Challenger, and scrubbed away. And off came all the stain - without waiting the usual 15 to 20 minutes for the stripper to break down the stain on its own. Then I just hosed off the deck. No pressure washer involved. I now have nice bare wood ready for new stain - and this was all done at 36 degrees F. These stripping products are supposed to be used only at much warmer temps. All this and NO SWIRL MARKS, either in the area that was sanded, or in the area scrubbed with the T & G brush.

you must have raked them out