Well, it was a strange experience, I don't remember exactly every my step. I have downloaded the image 3.0.3 E from this site, then I managed somehow to activate the PTS. And few days later I tried to record, and it greenscreened. I did not manually install packages, I did not tried it yet. So, I think, that "buggy" plugin was either built-in or downloaded via some official menu.
For the second point, on the previous PVR I had, the timeshift was always permanent and always "activated", AFAIR, and it was not a plugin, but an integral part of the system. I don't remember, if you could "deactivate" it, maybe yes via main menu, but the only reason for that is when you have no HDD. And, there was no "manual" mode when you had to remember to manually press "pause" to actually switch it on. It was either always ON or always OFF. So, this is why I think, the timeshift must be automatic (permanent), always on, and be integrated into all images on the system level. This will ensure that it works perfectly together with record function. If some hackers want to drive it manually, they could have that "manual" option in the timeshift configuration menu. But again, I think, by default, if HDD is present and mounted, the timeshift should be automatic and always ON. My experience with this was like someone who always drove automatic cars, bought super-new super-car. It turned out that this super-car is actually a powerful MANUAL 4-wheel-drive. It is like for windows user to try Linux.
Thank you for understanding.