I am trying to build a Title Block. The block will be inserted into any / all layouts in the same dwg file. Some of the text needs to be constant thruout the other layouts (i.e. Project Name, Client, Date). Other text needs to change from layout to layout (i.e. Drawing Number, Notes, Comments). Is there a way to have both dynamic text and regular text editable when I double click the block? Right now if I double click the block, a text box pops up and only lets me change the dynamic text. If I want to change the regular text, I have go into the block editor and change the text manually.
When you say "dynamic" text, I take it you are referring to block attributes. You can investigate a couple of options.
You can make "fixed" attributes CONSTANT in the block definition; those cannot be edited except from the block definition via BEDIT or REFEDIT.
You can add fields to block attributes which refer to attributes in other blocks, or text objects; when the source string is changed, every field that references that value will also be updated. Those can be prone to overwriting by users as they speed through entering attribute values.
Finally, you could use text in the block (as opposed to attributes) and have them refer back to a placeholder or proxy block with attributes that can be edited; problem with this method is the text in each title block instance won't show up in any attribute extraction.
I would suggest to build your title block through the Mechanical feature AMTITLE. Once you have it "behaving" the way you like, you can create a separate drawing with that title block inserted for your 2012 users. That way you will have the original in Mech to edit and improve, add features, text, etc., easily.