My slow cooker is rather elderly, but still works. It only has high and low on it. Generally, most of the recipes that are in the little book that came with it can be cooked on either temperature. Things just go faster on high. I like to start things out on high for an hour or two, and then turn it to low.
My crockpot has a removable ceramic crock. The crock is dishwasher safe. I have also used it several times to cook a large quantity of potatoes for mashing in the microwave.
The heating elements are in the sides, not the bottom. Because of this, I think that it would take a long, long time for the liquid to boil away - at least on low. I have no idea how a cooker would work with the heating elements in the bottom. It does seem like it would burn at some point.
If you decide to try the appliance that you already own as a slow cooker I think that you should do it when you are home and can keep an eye on it. Frankly, it doesn't sound to me like it would work the same, because of the location of the heating element. Still - what do I know? Best of luck trying this out, or in getting a real crockpot.