Why is mocha over-scaling corner pin data? I must be missing something

I’ve been working with Mocha for Final cut for a couple years now. I’ve switched over to Mocha for AE as I’ve just purchased AE and a newer version of mocha comes with it.
I’m tracking a computer screen that starts out of frame, enters frame, the fills the frame. Mocha has done a great job tracking this corner pin data for me. What’s not working is mocha is Scaling the new corner pinned footage to 193% in AE, making the CP-ed footage soft and pixelated once it becomes full screen.
The CP-Ed footage is the same pixel ratio and dimension as the original tracked footage.
Anyone have any ideas?

Which corner pin are you using?

This is because the surface is treated as 100% scale on frame 1.
We fixed this in version 2.5, but unfortunately the bundled version in CS5.5 is a release that is earlier than this (2.3).
The only work around is to use Align Surface on your largest zoomed in area and precomp on that frame, but it will still scale up from frame 1.
You can try using the other corner pin, but this will not support motion blur so you will have to use forced motion blur instead.

I’m using the effects>distort>corner pin.
And in mocha I’m exporting After Effects Corner Pin (not the one for RG warp)

There’s another solution that uses an Expression. You’ll first have to find out the largest Scale value and divide that number by 100. Let’s call this number, “Result”.
Then create an Expression in the Scale property with the following script -
It’s easy to find the largest scale value by taking a peek in AE’s Graph Editor by viewing the Value Graph.
Of course you could also upgrade to the latest version of MochaAE and take advantage of speed improvements.