I think you can only make filled regions on views (any views in the project browser)... not sheets...
I think you're like me a CAD user gone Revit... a lot of thinking to change...
You'll have to create a Filled Region within a Generic Annotation Family and then load that into your Project for use on your Sheet Views. You can use constraints and instance parameters to control the boundary of the embedded Filled Region in the Project.
Hi Shannon, and welcome to the Discussion Groups!
Drafting Views are created by going to View tab » Drafting View. It would probably be easiest to set the drawing scale to whatever your Plan View is set to. Before you create the Filled Region or Masking Region, go to Annotate tab » Detail Line. Draw a couple of random Detail Lines on this View so you can better locate it on the Sheet View.
Open your Sheet View. Locate your new Drafting View in the Project Browser, and drag & drop it from there onto your Sheet View. Overlay it on top of your other Viewport. Next you'll have to get rid of the View Title, so select the Viewport of the Drafting View and click "Type Properties" at the top of Properties. Click "Duplicate..." and name this new Type to something with "(No View Title)" and click 'OK'. Now Set 'Show Title' to "No" and click 'OK'.
Now, back on your Sheet, select the Viewport of the Drafting View again, right-click, and select "Activate View". This will enable you to delete those random lines and draw in whatever Filled Regions or Masking Regions you need. When completed, right-click and select "Deactivate View".
If you run into any issues or problems, don't hesitate to ask!
That was SO much help! Thank you very much! This stuff is just so not cut and dry! (I suppose I used to think about AutoCad too )
Again, Thank You! I may be back as I keep running into these little problems!!