Flat battery on 2016 R1200RT LE

[gogs01]

When I got back from my recent trip to Jerez, I gave the bike a good clean. I removed the panniers but left the top box on (it has a high level brake light and an interior light).
After cleaning, the bike went into the garage and I left the top box open to change out waterproofs etc.......
I obviously forgot about the interior light because the battery is now flatter than a very flat thing !
Plugging in the battery tender to the auxiliary socket doesn't appear to be doing anything so I'm going to have to get to the battery and fit a flying lead.


So, a couple of questions for anybody who has been down this road :
1.  Should the auxiliary socket still go "live" even with a flat battery ?
2.  Are there any issues with getting access to the battery and fitting a flying lead ?
3.  When (if ?) I get the battery fully operational again, is there anything which needs to be re-set, re-calibrated etc. ?

[T6pilot]

Battery is easy to access, right side cover off
I installed a powerlet fused plug, negative post on battery is very accessible, for positive I secured it to red post just forward of battery
On my bike I mounted the plug just abeam the rear suspension, in the black triangle plastic piece
Settings should be good once charged, clock if you have GPS should sync

[gogs01]

Battery is easy to access, right side cover off
I installed a powerlet fused plug, negative post on battery is very accessible, for positive I secured it to red post just forward of battery
On my bike I mounted the plug just abeam the rear suspension, in the black triangle plastic piece
Settings should be good once charged, clock if you have GPS should sync

Many thanks - that's my project for today.  ???