Any idea how I can resize the Messages area here?

I am trying to create this L+Today theme using Plazmic 4.6.
I am using the L_480x320.thm as my initial template and I added the Today-Messages icon/area as you can see in the screenshot.

But for whatever reason (that is beyond me at this point) it won't let me resize the right-side of the Messages area. When I drag the right-anchor point of the Messages are it just reverts back to the original dimensions.
What am I missing here?

Due to the fact that the Messages area goes beyond the screen it won't let me save/export the theme (gives an error).

Thanks!
Zax

Figured it out (might help theme n00bs like myself), it appears that the caret.png image needs to be resized first to match the desired today size.