In addition to the scope-connetor tip polarity (as Eddie Points out) you will need to be very careful with the Powerpole connectors! Normally, they are used by people who assemble them themselves and make sure that the polarity is correct. But you can assemble them one of two ways.
Powerwerx uses the "kinda" standard way of assembling them. That is, with the tongues of the connectors down, viewed from the front, the black connector is on the right. See the image here:
The MaxxPacks site shows the connector assembled the opposite way if you scroll down on this page:
If you aim the two at each other, you will ONLY be able to connect them together in the WRONG way. You will see that black mates with red and visa versa. If this is the case with the cable you receive from MaxxPacks, you can fix it relatively easily. First, if there is a metal pin in the hole in the top of the connector, you'll need to push that out with a jeweler's screwdriver or other small object. Then, you can slide one half of the connector forward and the other to the rear. You'll see that each half has tiny plastic dovetails molded into the surface. You can slide the two together again in the correct orientation using these dovetails. If you removed the metal pin, put it back in.