Hi Ulodesk,
There was no file attached to your last post, and the attachment to the previous one didn't include either an offending table or an indication of what unwanted Styles it imports.
I can't see why, given that the macro deletes all user-defined Styles, the "the majority of the invaders" would remain in the document after the macro has run. To retain your own user-defined Styles, whose names you say all being with 'K', doesn't take much extra code:
Code:
Sub CleanUpStyles()
Dim oSty As Style
For Each oSty In ActiveDocument.Styles
With oSty
If .BuiltIn = False Then
If Left(.NameLocal, 1) <> "K" Then .Delete
End If
End With
Next
End Sub
As for the Styles that are "in altered states from authors' machinations", you can remedy that during the paste operation that inserts the tables, by setting Word's paste options for pasting between documents to 'match destination formatting'. See under Word Options|Advanced > Cut, copy & paste.