To add to what Chris has said: " AU LIEU DE " means «instead of ". For example: "IL MANGE DU GÂTEAU AU LIEU D'UN FRUIT". = He's eating cake instead of a fruit. "En guise de" MEANS "By WAY OF".... Here is an example : "EN GUISE DE REMERCIEMENT, ELLE A ACHETÉ DU CHOCOLAT POUR SA VOISINE". In English: " IN ORDER TO THANK HER, SHE BOUGHT CHOCOLATE FOR HER NEIGHBOUR". Other example because it is not easy.... " EN GUISE DE REPRÉSAILLE, IL A DÉCIDÉ DE QUITTER LA FÊTE"... In RETALIATION, HE DECIDED TO LEAVE THE PARTY. I hope this helps you a little to see the difference between the two meanings. Practice, practice, practice :)

There is. "Au lieu de" means "instead of" whereas "en guise de" rather means: "as a replacement for" , a surrogate. He was standing on a barrel that he was using as a replacement for a podium. Il se tenait debout sur un tonneau qu'il utilisait en guise de podium.

I don't know.