Hi DPBaker,
1 - Platinum V8 and Super are the the only demo versions
2 - Yes, Plat 12 has the mm option with one decimal place
3 + 4 - To visualize the concepts, perform the following test:
Create an empty file (File--> new)--> Go to the floor tab--> you will see a small arrow at the right of the name. By clicking the small arrow you have the option of view / hide other tabs--> click in the small arrow--> the floor tab will be selected--> select also the foundation tab--> draw an exterior wall--> go to the properties bar--> be sure the foundation is selected--> in your plan, you will see the wall + the foundation--> put a window / door, etc--> Go to the foundation tab--> click on the small triangle--> foundation tab will be selected--> select the floor tab also--> your plan will look in the same way in the floor tab and in the foundation tab, right? --> Now, in the foundation tab--> click on the small triangle--> unselect the floor tab--> the wall and the foundation will disappear!
This means that you can draw a wall with or without a foundation, but you can't draw a wall foundation without a wall.
Therefore-->if you draw a wall foundation in the foundation tab, this step includes a wall, so if you draw a wall in the floor tab, you will be duplicating the process
5 - It is not a bug. Try to use the green helicopter for a controlled view. Anyway, the speed will be reduced with the elements' addition (walls, windows, roofs, 3D objects, etc)
Patricia