You were right about the SD card: although it shows only about 60 Kb with a proper card reader, SleepyHead was able to import a lot of data.
So here is my first SleepyHead report, hope you guys can tell me something useful looking at it:
The first picture is my worst 4th night with ordinary C-flex (although the other nights AHI were 11.44, 11.79 and 10.87)

Then I switched back to C-Flex+ and slowly increased pressure to 7 and 7.5. Last night's result looks like this.

I don't know why the flow rate chart appeared only for the last two nights (and many other graphs).
I still experience a headache and fatigue during the day((
And I'm quite worried about new inspiration/expiration time and tidal graphs, it seems my breathing is very shallow (if I use the word correctly) when I'm asleep.
Will be grateful for your thoughts;)