Welcome to the forum.
I figured someone who has a trail cruiser would have replied by now.
Anyway, the Trail Cruiser looks to be a fairly nice light weight trailer from the web page.
If you look under the unit, can you see the holding tanks? If they are enclosed, I'd imagine you would be OK into the 20's as long as the furnace is running.
If they are out in the open, it might not be hard to enclose the underbelly your self...
Dodge Ram dually laramie 4x4 w/jake, B&W, Brakesmart.
Kit Patio Hauler 394F toyhauler 5th wheel
Camo 680 Rincon, Green 500 Foreman, Blk twincam Roadking