Please Help!

I haven't built a lot yet, so I do not know. But everything I have downloaded that uses those gabled style roofs has some upper walls missing. Some basements can be seen from street level too. Flat and some other types of roofs, that I have tested out work fine. However, I have downloaded over 25 lots and the majority have that style roof, and they were from different websites and different creators. My roommate noted that they all had ceilings, and he deleted the ceiling and built a roof and it came out fine,but he was having a hard time trying to replicate the roofs that were on that particular lot. Sadly, the way the roof was styled gave the homes character. From neighborhood view, walls appear up, but in buy/build mode is where I am seeing these missing walls.

I found many more issues when I went to experiment. The lots that come with the game also have missing walls and they have fences across where the walls should be!! I never saw such a thing!! I tried building a house to see if I could try the roof to see if I still had the issue. However, I built a foundation first and then went to add my walls on top, like normal , but the walls went on the ground instead of on the foundation. I am not even sure if it was a foundation. Do they have bricks on the outside? This was like a decorative wood on the outside. Anyway, I tried several times to get the wall on the foundation and it just seemed to melt into the foundation. Then I tried to place a door and it would not let me. I also noticed the tool to make decks is missing from my game!! I am at a loss! I do not know what to do!