I think i got it. To generate a new style and then add it to a custom library folder on the C drive - start with an existing one; click the create button; edit it's properties; rename it in the uppermost field of the box; <enter>; click the update icon; drag it down to the lower pane.
Plus sign seems to be acceptable.
PS - allowable symbols in names for COMPONENTS (per my test):
~ !@ $ % ( ) ` - { } '