How to alter the transparency of the "Astrid Tasks" widget?

[SoCow]

Hi all,

I'm trying to build up my Astrid chops leading to the release of a
funky re-design of Astrid.
I can't figure out how you guys make the drawable/widget_frame.png
image transparent, can you help?

Also, is the appearance of the widget currently configurable through
the user UI? This is a feature i was planning on adding, just checking
it is not there already but hidden.

Thanks!