WH, Here's the lowdown on your Q's:

1) Are these all in a section of one bigger grow space and blocked off from each other?
The Moms/cloning/transition area is the right half of my closet in the spare room. This room is kept off limits to others, but is used for storage and keeping all my grow projects in a single part of the house. It is literally a closet grow... The left half of the closet is the flower room and measures 42 in x 24 in x 7 ft tall. The grow areas are separated by several layers of black visqueen, using Panda as the inside layer facing the girls. I (cheated and) purchased a HydroHut to use for vegging - it can be seen in the background... Check out the pics below

2) The emily's garden thing.....no issues with roots tangling together as the clones grow....supppose if they don't have any roots its no problem?
Emily's Garden is made by HydroFarm, and it is what some peeps model their own homemade DWC bubbler after (like me, Opie, et al). My clones grow in there for 2-4 weeks, depending on availability of other (limited) growing areas so they do have roots but not enough to worry about them growing together too much and causing problems. :thumbsup:

3) Curious.....how long does it take the clones to grow roots to the point that they would start tangling together?
It's been my personal experience that the roots can grow together after approx. 4-6 weeks after being introduced into this type of a setup. Your mileage may vary as results depend upon strain, health, and grower ability. In short they are out of there and in their perm. home before they get tangled up together. (I know how you like pics so I shot a couple of the girls that have been in there approx 2 weeks +/-)

4) How many plants do generally flower at one time?
This is an individual grower call. Last time I grew 2 Dominas in one of these type of homemade DWC contraptions that had a much bigger res (Emily = 2 gal, McGyver version = 6 gal), next to another identical DIY bubbler that held 3 Blueberry. After vegging 4 weeks and flowering 8 weeks the roots were tangled like a rat's nest... but not a big deal as they were intended to be vegged and flowered together as I did...

BTW, I got 4.25 oz from the Domina and 2.75 oz from the Blueberry even after encountering 100 F summer heat and colas falling over before trichomes signaled it was harvest time. And this was my first grow in 15 years or so. :woohoo: