Out for a blast last night on my 2017 Rallye 1200GS when 8 miles from home had an uneasy feeling pushing bike into the corners. Stopped and checked front tyre pressure. OK. Glanced at rear which looked OK. Road on only for ABS light to flash like mad. Road home at 25mph. Mile from home noticed rear tyre flat. 
Got wife to bring me a pump and got home OK. Had ridden over a newly gritted road which may have cause the puncture
1. Curious as to why ABS was flashing when rear lost pressure. Any thoughts?
2. Tyre felt very warm when noticed it was flat
3. Found where air was escaping. Centre of the tyre. Tyre fairly new so plan to get the tyre plugged locally
4. Garage will check tyre before plugging. Are there any tell tail signs that might indicate that I may have damaged the tyre side walls i.e. colour, signs of overheating, etc?
Any advice or pointers would be appreciated

Got wife to bring me a pump and got home OK. Had ridden over a newly gritted road which may have cause the puncture1. Curious as to why ABS was flashing when rear lost pressure. Any thoughts?
2. Tyre felt very warm when noticed it was flat
3. Found where air was escaping. Centre of the tyre. Tyre fairly new so plan to get the tyre plugged locally
4. Garage will check tyre before plugging. Are there any tell tail signs that might indicate that I may have damaged the tyre side walls i.e. colour, signs of overheating, etc?
Any advice or pointers would be appreciated