OK... well the code below seems to work (the text styles in the tablestyle dialog box change as does the text in the existing tables). However, I am still unable to purge the errant styles until I delete the tables.
Code:
(vl-load-com)
(defun c:CreateTableStyle()
;; Get the AutoCAD application and current document
(setq acad (vlax-get-acad-object))
(setq doc (vla-get-ActiveDocument acad))
;; Get the Dictionaries collection and the TableStyle dictionary
(setq dicts (vla-get-Dictionaries doc))
(setq dictObj (vla-Item dicts "acad_tablestyle"))
;; Create a custom table style
(setq key "MVVA STandard"
class "AcDbTableStyle")
(setq custObj (vla-AddObject dictObj key class))
;; Set the name and description for the style
(vla-put-Name custObj "MVVA Standard")
(vla-put-Description custObj "MVVA Standard Table Style")
;; Sets the bit flag value for the style
(vla-put-BitFlags custObj 1)
;; Set the text height and style for the Title row[/QUOTE][/QUOTE]
(vla-SetTextStyle custObj (+ acDataRow) "MVVA 1-8")
(vla-SetTextStyle custObj (+ acHeaderRow) "MVVA 1-8 Light Bold")
(vla-SetTextStyle custObj (+ acTitleRow) "MVVA 3-16 Light Bold")
(princ)
)