Maybe I am using this incorrectly, or maybe it doesn't do what I expect it to.
I open a part in Design Assistant, I select Tools - Find - Where Used. I click on <Click To Add...> in the "Look in:" pane, select the folder I want to scan, and hit "Search Now". Note, if I check "Include Subfolders", it seems to back up all the way to 😧 drive... not subfolders UNDER D:\Cone & Valve Fitting\PRS535 (which seems odd to me), and chokes on the search. This is what I get.
So, it SAYS "Found 3 file(s)."... but there is nothing in the list. If I hit "Save List", when I open the .txt file created, all it shows me is the path to the referenced SOURCE file.
What I'd expect to see is a list of assemblies that the part is included in. Is there something I'm doing wrong? Are my expectations incorrect? Is there another way to search easily for what assemblies a part is used in? Note: I do not use Vault.
I think you are using it correctly - but may not have set your project before selecting the component?
Start by opening Design Assistant, then going File > Close (if you have some file(s) loaded. Then set File > Projects to the required project. Now the Tools > Find > Where Used should work as expected.
You make a point of saying you don't use Vault. It's well worth investigating as it's much easier than the above - and it's included in Vault Basic so there's nothing extra to buy as you already have the software.