I've created book.xltx and sheet.xltx in the XLSTART directory to manage the
styles which are available in my new workbooks and worksheets.

However, this doesn't seem to affect the styles which are attached to
workbooks I open with Excel-New-Blank, or when I open a .CSV file.

How do I set up those style defaults?

Also, if I want to change many styles, must I click Home -Cell Styles over
and over to get to them, or is a persistent style dialog available?