Make the cookies: Whisk the flour, gingerbread spice, baking soda and salt in a medium bowl. Beat the butter, granulated sugar and molasses in a large bowl with a mixer on medium-high speed until light and fluffy, 3 to 5 minutes. Reduce the mixer speed to low. Working in two batches, beat in the flour mixture until just combined. Divide the dough between 2 large pieces of plastic wrap, flatten each into a disk and wrap. Refrigerate until firm, at least 1 hour or overnight.
Position racks in the upper and lower thirds of the oven; preheat to 350 degrees F. Line 2 baking sheets with silicone baking mats; set aside. Roll out one disk of dough on a lightly floured surface until about 1/4 inch thick. Cut out rounds using a 3 1/2-inch cookie cutter. Arrange 1 1/2 inches apart on the prepared baking sheets; cut a round out of the center of each using a 1 3/4-inch cookie cutter. Refrigerate until firm, about 15 minutes. Gather the scraps and cut-out centers and refrigerate until firm; reroll to cut out more cookies.
Bake the cookies, switching the pans halfway through, until just set, 10 to 12 minutes. Meanwhile, finely crush the candies in small batches in a resealable plastic bag. Remove the cookies from the oven and fill the centers of two-thirds of the cookies (about 12) with some of the crushed candies. Return all of the cookies to the oven and bake until lightly browned around the edges and the candies are bubbling, 6 to 8 minutes. Let cool 10 to 15 minutes on the pans, then transfer to racks to cool completely. Repeat with the remaining disk of dough and candies. You should have about 24 candy-filled cookies and about 12 empty cookies; you'll need 2 candy-filled cookies and 1 empty cookie to assemble each snow globe.
Make the icing: Whisk the confectioners' sugar and meringue powder in a large bowl. Beat in the water with a mixer on medium-high speed until soft glossy peaks form, 3 to 5 minutes. (The icing should be pipeable but not runny.) Press plastic wrap directly onto the surface until ready to use.
Assemble the cookies: Transfer the icing to a resealable plastic bag and snip a corner. Lay out 12 candy-filled cookies upside down. Pipe icing around the edges (don't get too close to the candy). Top each with an empty cookie; fill the cavities about halfway with sprinkles. Pipe icing around the edge of the empty cookies and set the remaining candy-filled cookies on top to create 12 snow globes. Let set 10 to 15 minutes. Pipe the remaining icing on the top of each cookie.