#\DeclareLyXModule[endnotes.sty]{Foot to End}
#DescriptionBegin
#Sets all footnotes as endnotes. You will need to add \theendnotes 
#in ERT where you want the endnotes to appear.
#DescriptionEnd

Format 8

Requires	endnotes

AddToPreamble
  \let\footnote=\endnote
EndPreamble