You can reclass objects for community lots using the SimCatagorizer found at
Sim Wardrobe. It's a very useful tool because, not only does it allow you to reclass objects for the various community lots (Vacation, Downtown, Studio Town, etc...), but it also allows you to change their price and where they appear in the catalog. It will also help you to identify items in your downloads folder.
For some odd reason I have it in my memory that certain items could be reclassed to work in Downtown, but still would not work there. For example, I could place a TV, but no one could turn it on. I think for those few items, I had to find items to download that had been converted somehow at various sites that have hacked items.
Addicted to The Sims since 2000.