I) If footnotes are restarting, most likely reason is presence of Section Breaks and the footnotes are being told to restart at a section break.

II) Generally when numbers are skipped it is because there are tracked revisions and footnotes 'marked for deletion' are still in the document. Fix is to accept tracked revisions.

III-2) Most likely the indentation, font etc was customised by the previous authors. There is a style for footnotes (Footnote Text) which should be modified to your preferences and you should remove local formatting from existing footnotes so that it matches the style.

IV) When changing the numbering to continuous, pay careful attention to the 'Apply changes to' option. It should be set to Whole document if that is what you wanted to happen.

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Andrew Lockton
Chrysalis Design, Melbourne Australia