[NEEDS INPUT] Roof trims are glitching out
First, I'm really impressed with your build. It didn't take me but a few minutes to realize what it was and you've really put some thought and effort into it. The stairs are a work of art in themselves. It's just great!!
Now, on to your issues. I was able to reproduce what you are seeing in a test build as well as on your lot.
The issue with trim in your imbedded pic happens with the roof trim regardless of whether the roof is on a diagonal or along the grid. Not much to be done about that one. You might try a smaller trim to minimize it though.
The issue with the little diagonal house at the back. I think the issue with the roof edge glitching is because the extended overhang/eaves are trying to go off the lot. The trim magnifies it but it's actually the roof edge that is doing it and the trim just follows the edge. I got it to go away by adjusting the overhang with the eave tool so that's one way to fix it. What I think you are doing with those 3 little buildings is greenhouses. Greenhouses typically don't have an overhang on the ends so it should look ok.
I did not see any issue like @Bluebellflora with the roof textures. It did the same thing with any texture I tried though it was a little easier to see with a solid texture.
But I think the best way to fix the issue is to move everything towards the front of the lot a couple of tiles to get that back corner of the diagonal building in a couple tiles so the corner isn't so close to the lot edge. It will be a bunch of work to arrange things to your liking but should fix the issue and allow you to have the overhangs on the little buildings too.
Hope this helps.
