The more I dig into the modding community the more I am impressed !!! (And the greedier I get in asking for more awesome mods) . I have two questions...

Is there a cheat that allows us to build wall pretty much anywhere? I am often frustrated when I can't build wall upstairs without supports....

Is there a mod that allows us to resize objects ?

Thanks

Not a cheat per se, but there's no reason why you have to KEEP the supports for a wall once you've built it, and basically as long as there are floor tiles, you'll be able to use the space. Just build enough columns to get the grid to appear on the level you need, construct whatever you wanted there, then get rid of the columns.

Yup, or draw a massive square on the lower floors, build over it and then delete the walls downstairs.

You can't resize objects in the game but if you are happy messing around in 3D modelling programs you could presumably do it easily yourself. I think there are a few items which have already been resized, usually plants, but if you have something in mind, search the object's name. Bear in mind though that anything other than a decorative item will usually have animations which won't look right when the item is resized.