How do you make opaque expressions? So you can place a text block within a staff and still read it? Well, I'll show you. It's very easy.
Enter the notes.
Using the Expression Tool...
...go to "Technique Text" and select "Create Technique Text."
Enter the text of what ever it is you want to say. It might be a fingering, or it might be an expressive instruction that you want to place outside of the staff, but would otherwise collide with a barline between staves.
After you have entered the text, but before you click OK, go to "Enclosure Shape." Select "Rectangle" from the dropdown menu, then click "Edit" and another dialog box will open.
Make sure the shape says "Rectangle" and then check the box next to "Opaque."
Change the "Line Thickness" to 0, the height to 0, and the Width to 0. This will limit the opaque area to just the immediate area around your text. If your line thickness is set to a number, then there will be a rectangle drawn around your expression (or whatever shape you have selected). You may want that in some instances, but not in this particular example.
Click "OK" on the Enclosure Designer dialog box.
Click "OK"on the Expression Designer dialog box.
Click "Assign" on the Expression Selection dialog box, and voila!
If you need to make a new one for a different fingering, instead of starting over from scratch, just go to the Expression Selection menu, select the one you had previous created, and then select "Duplicate." A duplicate entry will appear. Select that one and then click "Edit." You will then change the fingering, or whatever text, but it will maintain the other adjustments you previously had made.