Has anyone tried freezing cooked spaghetti squash?

Squashes and pumpkins of all kinds do Just Fine in the freezer, and thawed for later use. Yes, you will have excess water when it thaws, but it's really not the end of the world. It's easy to drain off most of that water, or use it to re-heat the squash. As an aside: this is how I have made hundreds of sweet potato/squash/pumpkin pies over the holidays: I start roasting as early as the end of October, "process" the veg to ready it for puree, then freeze. To me this is better than using canned puree of any kind.

No, I have not, but strongly suspect it would turn to spaghetti squash mush very quickly when thawed.