Straight copy from Revit Clinic:

Update Release 3 for Revit 2015 has been released to the App Manager. However, if the App Manager is not finding the update, you can download them directly from the links below:
Revit 2015
Revit Architecture 2015
Revit MEP 2015
Revit Structure 2015
Revit LT 2015 (64-bit)
Revit LT 2015 (32-bit)

Original post:
Revit 2015 – Update Release 3 – The Revit Clinic

Some objects in Revit are very difficult to mask over.  However, sometimes you just really need that quick method of masking something to save yourself hours of work.

Here is how you do it:

  1. Go to the Sheet view
  2. Make some text
  3. Set the text Type to Opaque and make the color just one very small step above pure white (253-253-253), otherwise Revit will make your ‘white’ look like ‘black’
  4. Draw some full stops (periods) to fill in the text box
  5. Put it on top of what you want to mask

In the video below, I show how this method works to mask a Color Fill Legend.

There is another method that is slightly more involved – you can put a shared Generic Annotation family with a Masking Region into a Drafting View and put that on the sheet.  Check out this link, where I reposted this method from The Revit Clinic.

The Revit Clinic has posted a nice little display order workaround for Filled Regions in Title Blocks.  I have a feeling that this workaround may also be useful in other situations…

1. Start a new Revit generic annotation family.
2. Cut & paste the filled region[s] into the generic annotation family.
3. Load the generic annotation family into the title block family.

While the display order may appear incorrect in the title block family, it should now appear print in the expected order once loaded back into the project.
via
Filled Region Blocking your Lines in a Project Title Block? – The Revit Clinic