Thoughts on Cuban style mojo ribs

Daniel - I have to admit I usually just wing it.. .

but if I want them like "Chinese Ribs" - not falling off bone then I go high 375 until they reach temp

But if you want them falling off the bone I would wrap tightly in tin foil place in a baking dish and cook about 3-4 hours depends on the size of the rack and your oven at 250, then unwrap, drain and cook another hour or so or so at 350 basting & turning them, to finish them off run under hot broiler for a few minutes.

I wouldn't put any liquid in the slow cooker- the ribs will release enough and if you have liquid it wills get soupy and weird-- I would lay the marinated ribs on a bed of yellow onions, garlic cloves & bay leaves - you will definitely have an non traditional cubano because the meat will be a different texture- but it will still taste good.

A slow cooker will braise your ribs, if you want a different texture then cook them in the oven-

To get really fabulous flavor de-frost them in a brine with "cuban" flavor (garlic, onion, bay leaves, sour orange- or 2:1 orange/lime) over night them dry them off really , rub with black pepper, garlic powder, onion powder ( or use low salt Adobo seasoning) -- cook in oven on a bed of onions and baste with mojo marinade.

Since the sandwich is already 'inauthentic' (big deal) I say just make a flavorful ribs dish and use that meat. As or more important, to me that is, is the sauce on the cubano - I use a chipotle mayo. If you place the ribs and mojo sauce in the slow cooker, you WILL be, by definition, 'braising' the ribs. I don't think i would go that route; too involved. Just marinade the ribs in the mojo and grill or broil. Chill til the meat firms up, so you can slice it thinly.
This is bobby flay's chipotle mayo recipe. I add some OJ concentrate and minced garlic to mine.
http://www.food.com/recipe/chipotle-mayonnaise-348370

You can ribs with a mojo marinade. Though the cuban sandwich doesn't really have that
flavor going on. I would just make a mojo and dress the ribs once they are on the bread.
Cheers
Buen Provecho