Cut the piece of marzipan in half. Color half of the marzipan orange by kneading in 1 to 2 drops of orange gel food coloring, or until it is a bright orange color and the marzipan is no longer streaky. Twist and knead the two halves together to create a marbled effect.
To cover the eclairs: Roll out a piece of marzipan to a 2-by-7-inch rectangle about 1/4 inch thick (the dimensions you need may vary depending on the size of your eclairs; you want a rectangle that is slightly wider and longer than the éclair). If the marzipan sticks, dust the work surface with a little confectioners' sugar. Use a pizza wheel or paring knife to round out the corners to create an oval that is large enough to cover the frosted portion of the eclair. Place the oval on top of the éclair, using the frosting to help adhere the marzipan securely. Repeat with the remaining eclairs.
For the heads: Take a piece of marzipan the size of a gumball or ping-pong ball (depending on how big you want the head to be) and roll it between your palms until you have a smooth sphere. Place the sphere down and use your palm to flatten it slightly on one side; this will make it easier to apply the facial features. Next, form the head into a teardrop shape. Repeat 3 more times, making a total of 4 heads.
For the legs and tails: Take another gumball-size piece of marzipan and roll it out into a log. Cut the log in half and then cut one half in half again; you should have 3 pieces. Repeat three more times. Roll the larger section of each of the logs into tails by tapering the end so it gradually gets thinner. Next, take the two smaller pieces from each of the logs and form the paws by flattening slightly and rounding out the end where the claws would be. Pinch the opposite end to flatten slightly where the paw will adhere to the eclair. Use a toothpick to indent the rounded ends of the paws several times to give the appearance of claws.
Put the candy melts in a small microwave-safe bowl. Microwave on 50 percent power in 15-second intervals, stirring between intervals, until melted and smooth. Transfer the melts to a piping bag fitted with a very small plain tip. Set aside.
For the ears: Stick 2 almonds slices, pointed side upwards, into each kitty head for ears.
For the eyes: Stick 2 mini white chocolate chips, flat side facing outwards, into each head to create eyes. Pipe a dot of the white candy melts onto the center of the chocolate chip and adhere 1 green sprinkle, vertically (use tweezers if needed) to the center of each. Repeat until all of the eyeballs are attached.
For the noses and mouths: Pipe a dot of the white candy melts in the center beneath the eyes and adhere a small pink heart-shaped sprinkle to create the nose. Pipe directly underneath the nose to create an anchor shape the mouth.
For the whiskers: Attach 3 white sprinkles to either side of each nose, pressing one end of each sprinkle into the marzipan on an angle.
Attach the heads, one at a time, by pressing them down gently on one end of the eclairs, so that the face is facing outwards. Attach the paws by pressing the flattened end of the paws to the eclair on either side of the head. Tuck the paws so that they hang forward off the front end of the eclair.
Attach the tails by poking a small hole with a skewer on the opposite end of each eclair. Insert the wider end of the tail into the hole, leaving the tapered end hanging off to the side. Curl the tail to give it some movement by gently twisting it until the desired look is achieved.