Hi
Yes, we understand what you mean by blurred background source. This is called the title background placeholder.
The reason the blur doesn't work when disabled, is because the group is off.
Anytime you want to use the title background asset, the group must be on.
But here, you are using the title background group as the source for a clone, which means you need to have it off.
So - the method of masking is the problem.
The pixel shift you see when the title background group is on - that means there is a 1 pixel x position parameter offset somewhere in your layers or often is is a .5 - look through your layers for the clone and look in position properties if it is no 0/0 for x and y, there is the problem.
Sometimes links for position can create offsets - this is a bug that has crept into motion in one of the previous released.
If you don't find a position parameter - then it may be from a position link
To save yourself going in and out of FCP to check for results - just add an image to the title background in the Motion template so you have a visual background not just the grey asset - then turn your links off and on until you find the one that creates the pixel shift.
Turn off align to when do this - align to is very system heavy - if Motion gets slow as you click between links - this is the align to behavior - ..just a side note here - anytime you work in motion and clicking between layers and links becomes slow - turn off the layers and the keyframe editor - f7 and f8 - that should restore smooth UI operations.
(don't know why - but it does)
I asked if it was supposed to animate, because in FCP - it wasn't animating.
So, from your last report, it sounds like Karstens method solved the problem with the blur not working - is this correct? I haven't reviewed the tutorial - but I will make a Motion template to demonstrate how I would do it if the problem remains. Let me know.
To explain the pixel shift - make a new title template - no need to add anything - just go to the title background placeholder and change the x position from 0 to 1, or to .5
Now publish that - and go into FCP and add the title on some media - you will see the media jump
I couldn't tell where the pixel shift was happening from your screen shots - but do that little exercise and it should be clear why that happens - and it is something that can happen a lot.
With this bug, sometimes when you just duplicate a template, ..the duplicate title background asset will suddenly have .5 and .5 in the y position - so, always check the title background asset to make sure the x and y are 0/0.
I'll check back to see if you have responded later.
Some other general observations
If have a fade in and out behavior on a parameter - and then you have published the parameter - this can cause issues.
Publishing the checkbox that makes turns layers or behaviors on and off is not ideal. As you see, you end up with locked parameters published and means you can't remove it directly from the inspector - if it works for you now, it works - that is good, but if you want to learn better ways to make something active and not active - let us know and we can show you.
If you make a post to ask about how to create section dividers for organising your published parameters - I will be able to point you to a tutorial for that.
In the original project file I sent you - I already set up the widgets for you - for removing the 'custom' from the the menu. If you want to see a screen recording of the process, I can do that and post it here.