Tapwave Zodiac messed up screen (help!)

Howdy folks. So I got a very cheap Tapwave Zodiac for $20, however the battery is long dead. I buy a power cable off ebay and it powers up fine. Like an idiot I decide to get a replacement battery (one of these here.) Problems started after replacing the battery.

• First attempt at replacing battery: Take out old battery, put in new battery. Screen goes completely white. Still can hear noise when I tap the screen (I'm assuming it's going to the "set the date" screen.)
• Second attempt: Replace old battery - screen shows up, but slowly fades out to white. Same thing happens.
• Third attempt: Read on internet that ribbon cable might be loose. Take out ribbon cable and reset it. Insert old battery - everything looks good! Suddenly after a few seconds the "Battery extremely low" warning comes on, then console emits a horrible screeching.
• Fourth attempt. Put in new battery, re-seat ribbon cable. White screen, no sound when tapping.
• Fifth attempt. Put in old battery, re-seat ribbon cable, attach power cable. White screen, noise when tapping.

At this point I'm at a loss. Anybody out there know anything about these consoles? Can you tell me what I'm doing wrong? At this point I just want to get it back to normal, forget about changing the battery.

thanks in advance.