Gerard,
Search on Axialis. They make an icon editor that can edit a FPW 2.x ESL file. Per George Tasker's comment about legality, I don't know if this is in fact legal but I have never seen comments from Microsoft or others indicating that it wasn't legal. The ability to change an application's icon is consistent with other MS tools so I can't imagine MS having a problem with this. Plus the fact that FPW is no longer a MS supported product.
Good luck,
Malcolm
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I am trying to change the icon in the .ESL file but the icon program I am using is running into some problems (MicroAngelo). Is there another Icon changer around that maybe I could use?