I am making a groom's cake for my future son in law (June 28). I plan to attach an edible image to a fondant backing.  I have fears as it's my first attempt with an e.i.

1.  Can I attach it to the fondant backing and store it for two days before decorating the cake?

2.  How should it be stored before I am ready to place it on the cake?

3.  Can it be placed on the cake 24 hours before the reception?

4.  Once fully decorated can the cake sit in an air conditioned room 24 hours before the reception, or must it be refrigerated? I am using a buttercream (no butter or dairy)) frosting.  Thank you!