Margarine, If Melted and Resolidified, Does It Need to Be Refrigerated?

I am with Anna C on the replacement of the margarine with butter. There is nothing good about margarine. My friend has a nightmare story of where she put a couple pats of margarine in a pan, got a phone call and turned off the stove. When she came back it was like a sheet of plastic! ICK! So I personally don't use anything but butter because I can't see putting that ick into my body! Butter is more natural and fine if used in moderation. I would try the recipe with butter instead which should have no problem freezing.

I own a restaurant and am certified in food safety. It will not have to be refridgerated. You may leave it out, whether it has margarine or butter, your fine.

As mom always said, "It's better to be safe than sorry!" I'd put it in the fridge covered loosely with foil if you don't have a cake cover. I know both butter and margarine boxes advise to Keep Refrigerated.
On the other hand, during this time of year when it's cool in the house, I've left margarine out overnight and used it the following morning for baked goods. Nothing bad happens.
If the cake has raw eggs you should refrigerate it.

I agree with replacing it with butter - I use real butter in all my baking and feel it makes a big difference. Margarine is great for toast, rolls, etc. Sounds like an interesting recipe.
That said - I have often left margarine out and never had a problem.

I don't know the answer to the refrigerator question, but can you share the recipe. I am always looking for no-bake recipes for my son. He loves to cook, and gets frustrated when I have to take over and put stuff in the oven.

Since the cake is never baked and it has margarine in it, I would guess it needs to be kept in the frig.

I think it can be left out unless you keep the temperature in your house in the 80s nowadays.
In the 60s and 70s, the margarine won't melt. Margarine doesn't get rancid the way butter might.
With margarine, you don't have the risk of salmonella that you might with eggs.
Having said all that, I would probably replace the margarine with butter in the recipe because of my concern with the transfats in the margarine.
Enjoy either way!!