Ok, since everyone seems to be wanting to point out all the reasons I should have done it differently....
Clutter free means that the top of the table has the mill on it, and nothing else. It stands less than 3" tall. No motor/drill, fans, boxes, etc. Makes for a much neater design, and allows me to have a cover over it to keep out dust & dirt and be a flat surface when I'm not milling, and that cover is not 6 or 8 inches higher.
With the mill on top, accessing the hopper screws, and gap adjusters is painfully easy. Underneath would be significantly more inconvenient. And my receiving bucket slides into a captive ring that keeps it in position with no gap whatsoever. The only dust I get comes out of the hopper at the end.
I use that flat surface of the top primarily to support my scale, and whatever bin I'm measuring grain from, side by side. Once I finish weighing out my grains, I put the scale back into a compartment under the milled grain receiving bucket, open the lid, mount the hopper (that stores under the motor) click the switch and mill the grain. When I'm done, I remove the hopper and close the lid, and roll it out of the way. The picture below should make this pretty obvious, although it was not finished at that point. The lid is not shown, the motor cover/switch is missing, and it's not painted. You can see the motor cover and paint in the earlier picture.
Bonus uses I'd not thought of in advance:
When I finish my boil I lift the kettle onto it, roll it over in front of my sink, and hook up the chiller. Once chilled I drain into a carboy. This way I only have to lift the hot wort about 18" of total distance. Once I plumb water to the "brewing tree" I won't need to do this anymore. The lid is covered with Formica, and I put a towel on it in case of any spills or splashing.
It also supports my bottle washing station (large bin) while in use. This connects to my RIMS & pump.
And, it provides a place to store several items on top when I'm not brewing to keep things consolidated, such as the bottle washing station, and buckets/carboys.
So, getting back to my original question, has anyone else used this motor with an indirect drive?
At this point I'm pretty sure I'll go back to the chain drive and add a guide so it can't jump on the sprocket, and with near zero play. I think part of the problem was slight misalignment between the sprockets, a little play, and a little wobble of the welded sprocket. With the new output shaft I made I can align it perfectly, and it will turn true as well.
And before anyone points it out, no the tension pulling down is not an issue. This mill has roller bearings, and I have a pillow bearing right at the sprocket to support it against that downward pull.
After the original sprocket failure, I jumped on the timing belt/pulley idea as I use them on several other business related things I've built, but none of them have any measurable torque. That is the downfall of this use, and I'll know better for future projects.
An additional bonus to indirect drive - I used a bigger sprocket on the mill, and increased the RPM from 110 to 145 (or higher).