Technical questions regarding Sleepyhead

[On the virge]

• Using data export of Sleepyhead, one of the parameters is titled "Pressure 1%". Can anyone shed light on this value? I presume it might be 90%?
• In the backup done by Sleepyhead, there are two folders: Events and Summaries. I presume these are stored copies of the "Events section of the Daily Data" and the CPAP Statistics table neither of which are completely in the exported data. Is there a program that will read these files hence allow data manipulation and analysis? I am mostly interested in the events data (time of event and duration). I am curious to see whether there is a correlation among days between time of onset and time of day for example. Silly example would be (assuming I lived near a railroad track) whether the onset of an apnea consistently happened at the scheduled passing of a freight train. I'm just curious.
• What/where/how do things change if "Keep Waveform/Event Data in Memory" box is checked in the Import submenu of the Preferences Tab? Does that allow the export of the Event data such as time and duration?
• How does one interpret the "By Pressure" waveform? I understand the top line displays minutes at the various pressures for the whole night or whatever time frame is selected. I don't understand the meaning of the colored lines that rise and fall, again for the whole night or whatever time frame is selected. They seem to be color coordinated with the various events but the numbers under the various pressures don't seem to correlate with other data. The slope of the lines is displaying something but I'm not sure what it is.
• Recenty I installed Encore Basic as a second view to Sleepyhead. I find it tantalizing but unsatisfying compared to Sleepyhead which I embrace. I compared the minutes at pressure for both programs (the By Pressure "waveform" in Sleepyhead and the Daily Events per hour matrix in Encore Basic's Therapy Details Report). The numbers are quite different. Since they are working with the same data, I would expect approximately the same numbers. For example on Feb 6th Sleepyhead showed 365.2 minutes at 8, 32.8 minutes at 9 and 1.1 minutes at 10 for a total of 399.1 While Encore basic showed 318.3 minutes at 8, 74.3 minutes at 9, 6.1 minutes at 10 and 0.4 minutes at 11 for a total of 399.1. I can see this difference leading to different values for the median pressure, the 90% pressure value, etc. Does anyone have any ideas?
• In Sleepyhead, the CPAP Statistics screen displays under Leak Statistics
% of time above Leak Rate threshold 2.22%
While the Overview graphs display Large Leaks (If selected) and for the same day the graph "tool tip" displays "% in LL - 2.86"
Any thoughts.
• For last night, Sleepyhead Daily Details in the colored bars area shows Large Leak =1.03% which is the % of time in Large Leak yet farther down under Statistics, it shows Time over leak redline =0.000%. Admittedly, I don't know what the leak redline definitely means. On the 16th, Sleepyhead said time over leak redline was 2.522% yet I had o large leak events and Large Leaks = 0.00%
• Finally, my prescription is 8-12; however, the minutes at pressure data show data in discrete cells (8,9,10,11,12) that is why the headers in the attachment are what I presume they mean. Unless, the machine really provides pressure at those discrete pressures. But that makes some of the other data strange, for example, reporting 90%pressure less than 9.456 which would be either 9 or 10 for discrete pressures. Also I use the ramp which runs for 20 minutes, yet neither program shows minutes at pressure less than my prescription 8 even though total minutes presented really equals total system time.

I would appreciate any insights.