Can the Crusting Buttercream Icing (VIVA Method) be used to add borders to NFSC? Can they be bagged with this icing? Stacked? I have never made this icing, just used the commericial kind from my local cake store. Its yummy, will; this recipe taste like the commerical kinds?

No, it will not dry enough to "stack". To dry stack cookies, only royal icing or rolled fondant will work for great results.

No, I believe it'll be too soft, even though it crusts, to use on cookies that'll have to be stacked.

Toba Garrett's icing works well. Dries hard enough to stack and won't chip a tooth.

http://forum.cakecentral.com/cake_recipe-2119-Toba-Garretts-Glace-Icing.html

You can also try rolled buttercream