You might try welding gloves or fireplace gloves. (fireplace gloves tend to be longer, and might go up to your elbow).
They're typically made of suede, with an insulated lining. I use them instead of pot holders, but they also come in handy when I'm doing large amounts of grilling (once a year, for our departmental picnic, cooking for a couple hundred people).
The fireplace gloves also come in handy when camping, as you can reach in to move logs if you're quick about it. The only issue is that too long of exposure to hot, dry heat will cause them to harden up and lose their insulating properties. I have to get a new pair every few years or so because of the way I use them.
I also have some really heavy duty rubber gloves that I got more as a joke -- I'm not sure if they're for haz-mat purposes, or what, but they come in handy for when I have to deal with hot but wet things. I've also used them when dealing with cleaning out the fridge at work that had gotten pretty scary (it was near a conference room, and people using the conference room would leave stuff in there and forget about it). I've seen similar gloves, maybe not quite as thick, though, at a restaurant supply store near heavy rubber aprons for the people doing the washing up.
And, if those still don't fit your preferences, you can find silicone potholders ... they've got good grip, and you should be able to roll it into a cone around your piping bag.
To be precise, the lollies are not melting. They are absorbing water from the air.
If you're really just crushing the lollies (not melting them and re-casting them into sheets of "glass") then you're accelerating the absorption process by increasing the surface area.
Does it need to be out in the open for five days? I'm surprised the gingerbread hasn't gone soggy (actually, I'm surprised it's not been eaten). I would consider putting it in an airtight box until it's ready to serve.
Otherwise, you might be able to make the windows last longer by reducing their water content. Put the crushed lollies in a pan, bring them to the boil and let them simmer to lose more water. Use a sugar thermometer to find the necessary stopping point. Be careful not to burn the sugar. Then pour onto a flat greased surface, to solidify into "glass".
Best Answer
Using melted hard candy, you are at the mercy of the ingredients of the hard candy manufacturer. I like to make my own sugar glass. Here is my recipe for sugar glass:
I always supplement it with cream of tartar and corn syrup. The cream of tartar stabilizes the mixture and the corn syrup helps the glass stay clear. Sucrose (table sugar) is a disaccharide (two sugars) of glucose and fructose. Most cracking occurs when when there is a structural defect due to crystallization. Applying acid (cream of tartar) causes the sucrose to break down into its component sugars and stabilize.
Also remember that heat and humidity are the enemy of sugar glass. Do the best you can to control the environment of the sugar glass.