In regards to the library question...Yes, you CAN open more than one library at a time. In fact, I have never reached a limit of how many can be open at once, and I've tried!
The following is a bit long-winded, but if you need to know how to do it, it's pretty in-depth...
In order to make a new library with all of your personal text/shapes, delete out all of the text/shapes you don't want from the score expression pallette*. Now, save the libraries (File menu) you want (they should be under both shape AND text expressions I believe).
When you open a document with the libraries you want to add to, say a Default file, select Open Libraries (File menu) and choose the two you just created. In order to save that as one big library, do the same routine for Save Library you did before. It's a very flexible program option.
*some of the shapes ( such as / and ) are a bit difficult to get rid of, as they are used for playback. The best way to get rid of those is to delete them from the edit/create area of the score expression dialogue box. Then text expression designer dialogue box -playback options - execute shape - select those shapes, and delete them. them you can delete them from the main shape palette under score expression.
