How to keep Glaze for Gingerbread cookies translucent

To expand upon baka's comment: this would taste good without the cumin too; it'd just be a simpler flavor. You can then replace it with any other spice that appeals to you, since pork's flavor isn't going to strongly clash with many spices. ElendilTheTall's answer suggests one option; I'm sure you can come up with others. This gives you a chance to make your pork fit well with whatever other dishes are in your meal.

Use the tapioca starch, or, if you cannot find that, another tuber starch. It is more waxy than cornstarch, and therefore better suited for a glaze. It will give you a glossy, transparent appearance.

Cornstarch is a mealy starch, with high amylopectin content, and creates a soft, fluffy, somewhat cloudy mass, not as glossy or as transparent as waxy starches. By the way, it shouldn't have an off-taste if you cook it through.

I guess that most recipes haunting the Internet use cornstarch because it is so much more common in a home kitchen, and the home bakers found the result good enough for their purposes and/or were not aware that tapioca will give them a better end product. As you describe that you want a really good glaze, go for the tapioca.