I will be making some large flower cookies as corporate gifts that consist of each petal as a individual cookie. It will be delivered in a decorated pizza box - so a flat surface - but the petals are layered on each other. I need to "glue" the petals to each other so the design stays in tact. The obvious glue would be royal icing - but it dries so hard that when someone would try to remove a petal, it will break the cookie. I need something that holds the cookies together - but will release easily and without damage. Any suggestions?

How about melted chocolate? It could be white if you have white icing on your cookies or you could use the colored candy melts...

Never thought about chocolate! Good idea.  Thanks!

Some dried up toothpaste ought to do the trick.  Did that once for my son's birthday party, all the kids loved it.

Buttercream would probably be my choice. You could also try glaze icing. It doesn't dry hard like RI.