Strange Earth Wire Location - Battery/Aternator/ABS lights -

Hi All, the battery died on my recently aquired 1998 a8 - in the boot have to remove top panel to get to battery and accidently pulled connection from a brown (earth?) wire to the back of the plastic panel.

Charged battery then took for a drive to get a new connector for the above panel. After about 10 mins of stop start driving the 'battery' light on the dash illuminated - i assumed this was warning me of low battery voltage but according to the owners it's alternator warning? Will a low battery throw this warning up or is it likely to be the alernator?

THEN - stop in traffic and the abs warning light would flick on and off everytime i pressed the brake - until it finally stayed on permanently!

Got car back - have reconnected the earth wire and will put on for a decent charge in the morning.

a8 has driven fine until now for past 2 months with no warning lights etc. It has been sat funused for a week hence the flat battery.

So i'm wondering what could be causing ths strange run of bad luck and if there is anything i can do to check what might be causing the problems?

cheers for any help Fraz