Tuning Tips
There's a math formula in the MAX8212 datasheet for figuring out what resistor values give what trip points, or you can trial and error it, my preferred method.

Things you'll need to test/tune it:
-a voltmeter (preferably a DMM)
-power supply with variable voltage, being able to limit the current is nice to fine tune
-a test load (light bulb, motor etc. something you can see when it is on)
-small flat blade screwdriver for the pots

It's a bit like tuning a guitar. Get the trip points roughly set, then fine tune them back and forth. If you use the suggested pots and install them with the writing facing outwards towards the board edge, they turn in the direction you'd intuitively want them too: turn CW for a higher voltage and CCW for a lower voltage. Say you want to set it to turn on at 10 volts-ish and then turn off when it falls to 5 volts-ish, using a DC motor for a test load.

I'd go at it something a little like this, but I'm sure you can find other ways:
Rough Tuning:
1. Before powering up, crank the low trip pot a bunch of turns CCW and the high trip pot a bunch of turns CW. This spreads out the voltage range, it's easier if they aren't close together or somehow reversed (high trip lower than low trip), though I'm not sure if that's possible.

Hook up the motor to the output and the power supply set to, say 6ish volts to the input. Connect the voltmeter to the power supply if your power supply doesn't have a display. Let's set the high trip first...

2. Is the motor spinning? If yes, the high trip is set too low, go to step 3. If no, that's good, find out what the high trip is set to... go to step 5.

3. Turn down the voltage until the motor turns off. Note the voltage. This is your approximate low trip for now. Continue to step 4.

4. Crank the high trip CW a whole bunch of turns... go to step 5.

5. Slowly turn up the voltage until the motor turns on or you get to 10 volts, whatever comes first. 

If the motor turns on before 10 volts, go back to step 3. 

If you get to 10 volts and the motor is still off, turn the pot slowly CCW until the motor turns on... the high trip is now set to ca. 10 volts. Continue to step 6.

6. Now we are setting the low trip pot. It is basically the mirror process of above. The motor should be on and the voltage should be around 10. Turn the voltage down until the motor turns off or you hit 5 volts, whatever comes first. 

If the motor turns off above 5 volts, the low trip is set too high. Turn the voltage back up to 10 volts and turn the low trip pot CCW a bunch of times. Go back to the start of step 6.

If the motor is still on at 5 volts, the low trip is set too low. Turn the low trip pot CW until the motor turns off.  Now you should have the low trip volt roughly set as well. Fine tune if you wish.

Fine Tuning:
If you can limit the current on your power supply and have are using, say, some super capacitors to store a charge you can choke back the current to a controllable limit and watch the caps slowly charge up to the high trip voltage on the DMM. For example, I used about 500mA with the array of 360F caps. You can then fine tweak the pots as needed in a manner similar to above, but you will be able to be more precise by observing the slowly changing voltage. Remove the power supply and watch the caps discharge through the load to do the same with the low trip voltage.

These are suggestions only, based on what I've found works for me. This will take some trial and error, patience and persistence to get it right the first time. Then it gets easier.