For Number 1.

1.
Place the "Builders Help" on the floor of the desired house size


2.
Stack 5 Rows from Concrete Plate (Slaps) on it



3.
Place the Brick FW 275 on the edge and remove the plates and Builders help underneath


4.
Now you can place your Brck FW 275, Door Frames and what you want on the ground and fill the space with DIW 25


5.
At least you can place your door, window frame into the space


6.
now you can design your floors and ceilings