[ChevyGuy]

The question is - do you have any remaining problems? Unlike older cars, the Cruze is completely computer controlled. Yes, even the hazards and trunk latch. I would take the opinion of the local parts house people with a large grain of salt. What they say is true of older cars where the trunk and hazards are controlled by hardware switches. But that's not how the Cruze runs.

 

[ChevyGuy]

however anyone with half a brain knows a dying battery should not effect things like hazards or my trunk opening, not to mention the car playing opossum when I try and unlock/lock it from my remote.

The trunk latch is controlled by the BCM (Body Control Module aka "computer"). The remote is just a command to the computer.
The external lights are controlled/run from the BCM. The flasher switch is just a command to the computer that run the "flasher" routine in software. (There is no flasher in this car.)
The door locks work like the trunk latch. The command received by the receiver is passed along to the BCM which does the actual controlling.

Anyone with experience with PCs knows that a bad power supply can cause all kinds of illogical and random behavior.

But there's something else to consider: Do you have something plugged into the ODBII port? Perhaps one of those insurance dongles or add-on features? It may be causing problems. Anything plugged in there is on the computer's bus and can cause all kinds of problems if it's less than great.

 

[ChevyGuy]

Check your grounds. If you have access to a multimeter, check the resistance from the top post to where the battery ground cable attaches to the chassis. You should see 0.0-0.1 ohms. If not, check the connections at the battery and chassis.

I'd prefer to do a voltage test while the car is running. With the meter between the battery terminal itself and the ground screw, you shouldn't see more than 0.1V. Probably a lot less then that.

Since the connection can be intermittent, you may want to check it at different times.