Flat battery on 2016 R1200RT LE - the sequel

[gogs01]

As per my earlier thread, the battery on my 2017MY RT was completely flat due to my leaving the top box open (there's an interior light which takes a long time, but eventually drains the battery completely).
The battery tender wouldn't charge the battery via the auxiliary socket but a flying lead straight to the battery did the trick. 
20+ hours charging later, the battery looked to be fully charged, the bike started on the button and everything seemed to be working.  I did have to re-set the clock, and the date was on 2080 !!  A quick re-set there too and I was ready for a run to Biggar.  After a round trip of over 200 miles the bike appears to be entirely normal, so now I just need to remember to keep the top box closed when the bike is parked up !