electrostatics - Why does Hauksbee orb or a similar device produce light?

This essentially fits well to the question asked earlier but had to placed as a separate question... An interesting and detailed answer was provided. However, there are few points, originating from my own observations, that can complement the discussion started before and pose some questions.

Please check this for the context: Why does Hauksbee's electrostatic machine produce light?

I am looking for a possible explanation of ages-old experiment done by F. Hauksbee in 18th century. Briefly, he observed appearance of light when applied his fingers to the wall of rotating evacuated glass orb.

My observations.

I have a glass ampoule (cylindrical shape) with pressure as low as 10^-6 Torr (a glassblower made one for me but I havent seen the pressure gauge personally so took what he said me for granted). I experimented with the ampoule. It did glow after I rubbed it with hand or finger OR dust cloth AND crispy plastic bag worked perfectly. To observe the flashes of light I had to be in a nearly complete darkness. Indeed, the flashes of light appear in response to mechanical "stimulation", however, after the ampoule was significantly "stimulated", few flashes of light could appear spontaneously. I am v curious about this phenomenon and if there's any sensible explanation to it from conventional science. Clearly electrostatics causes flashing but if the charge just "sits" on the surface, nothing happens. One only need to lightly touch highly "stimulated" ampoule to cause amazing flashing just under your finger or sometimes it involves the whole interior of the ampoule.

Now questions.

1. 
   

   How can glow appear at this high vacuum if, as it was explained, certain not v low gas pressure is necessary to explain this by ionisation mechanism? And 10^-6 Torr is certainly v low vacuum.

   
   


2. 
   
   

   It was suggested that electrical breakdown of the rarefied gas inside results in the avalanche of free charges and this is turns causes ionisation. Then why do flashes of light appear inside (as was asked initially) when we touch the ampoule from the outside, sometimes involving the whole ampoule and sometimes being localized? I am quite sure that when we touch the ampoule with a finger or a cloth used before for the "excitation", the charge on the outer surface recombines with excess charge on the cloth or just flows to our body. Hence it is the minute currents that actually relate to the flashing. And this currents flow externally to the ampoule. There should be no uncompensated charges on the internal walls, only some charge separation induced by el. field.

   
   


3. 
   

   Our body is quite conducting comparing to fabrics, paper and plastic. Yet it causes "excitation" of the ampoule as well. Why?

   
   

Feedback will be v much appreciated!