you can also make royal with the "orgran no egg" egg replacer, same as royal icing but use the no egg in place of egg whites..

(I use meringue powder in my royal, which has dehydrated egg whites.. not sure if thats still out?)

you could also use a glaze icing, which will set like royal, icing sugar, corn syrup (glucose syrup) and a dash on milk, can still be coloured etc..