solver

On the first floor, select the room under the stairs -- select the stairs then Tab to select the room. Give it the Open Below room type.

There are no stairs in your plan.

Thanks. Did you try the Open Below room?

If the auto stairwell tool is not working, you can create your own using an Open Below room as that's all the stairwell tool does -- along with placing railings.

Yes

I don't think the program will auto build your roof. Dormers will not work because they must fit on a single roof plane. Why not a manual roof?

What's wrong with the roof in the image you posted? The program is poor at doing gambrel roofs, so you may need to manually edit them.

You are describing a Mansard roof. Look at the Roof Styles panel in the Build Roof dialog.

If this is what you want, then select the stair sections and landing and move them over. You may need to hold the Control key (free move) to drag it into place.

The dormer tool is a pain, but it does work if you follow the instructions. Consider creating a simple one room structure and getting the dormer to work there. then take what you have learned and apply it to your plan. You can also do the dormers manually. Again, try this in a simple practice plan. On the 2nd floor, draw walls where you want the dormer forming a room. Set the ceiling height of this room as it should be, and set the roof pitch in the front wall. You will have one room on the 2nd floor that is everything but the dormer. Set its ceiling height to 1-1/2". Build the roof. The program will build a dormer. Once the dormer and all other roof planes are correct, turn off Auto Rebuild Roofs, and set the 2nd floor ceiling height correctly. Note that you do not need to make the 2nd floor room 1-1/2". If your house has taller walls then use that dimension. The key is to experiment with simple plans to gain an understanding of how the program works.

What are you wanting to snap to what wall? Attaching the plan file (close the program first) lets others make the best suggestions.

You just need to fiddle with them. drag them together etc. Check the links above for videos etc.

The first one try drawing in a wall to close the gap. The 2nd -- post the plan file.

Draw 2 stairs and then drag the edge together. Fiddle with them a bit and they should connect.

Draw a straight ramp, select it and click the Change Line/Arc icon. Shape as required.

Delete the slab and walls. All you should need are 3 invisible walls outlining the porch. Set the room type to Porch and make sure Roof Over is checked. Set the end walls to Full Gable and the front wall to have a lower pitch.

Read up on how the material painter works. There are multiple modes -- you need to select the correct one. Dormers work like most other objects, you select it, open its dialog and make changes. You also have Default Settings that may be changed -- set roof to shed for example. I don't understand these two. Do you have better images of the house you are modeling? When asking about roofs, using a Technical Illustration with the patterns off (3D>Toggle Patterns), gives a clearer picture. And posting the plan file will help answer your questions.

If the concrete in front of the house is a room, select Roof Over This Room to start. Lots of good info linked above.

Change the hip to a gable.

There are training resources available (linked above). Have you reviewed them? You mention creating a shed dormer. What specifically is the issue? Same with changing the roof to metal. What are you doing that does not work? Attaching the plan file is often helpful too. Close the program before attaching.

Google 3D Warehouse if you cannot find something in the Bonus Catalogs.

Have you checked the Bonus Catalogs available for download on the Home Designer site? Library>Get Additional Content Online

Not in the Home Designer line.

Exactly. Place the tub in the countertop, then shape the countertop to fit. Once you understand the CAD tools used for shaping things -- countertops, slabs, roofs etc, it goes quickly. You might want to block the tub and countertop when yo are done.

Use a Custom Countertop. They may be shaped where soffits cannot. I show a gap only so you can see how to form the basic shape. You would close the gap.