Let me see...

Question 1: Did you overclock?
Answer: "the device is just the same config (except for adding CSSU-thumb) then until 2 months ago..."

Err... does that mean yes or no?

Question 2: Did you check filesystems for corruption(you can check fsck logs in /var/log/ )?
Answer: "i'm a Linux user (professionally & privately) for over 15 yrs... i know how to take care of a Linux system, thanks for asking."

Err... does that mean yes or no?

Question 3 (implied): Did you check the battery?
Answer: "again, ceteris paribus..."

Err... does that mean yes or no?

Question 4: Could you install syslogd and sp-rich-core and provide coredump next time crash/reboot happens.
Answer: "i'm going to re-flash the other one without CSSU-* & think about whether i'm going to leave this one w/ CSSU-thumb
even IF i do, it is going to go back to the "alarm-clock" & prepay calls status... if it still crashes under those circumstances, reformat..."

At least this one is clear. I take it to mean no.

And yes, I have looked though the complete list of your posts, including in other threads and no, I have not found anything specific. Argumentum ex silentio comes to mind. I am sure you are familiar with it, since you like Latin phrases so much.

Ab imo pectore, vade in pace.