mouse touchpad frozen on live stick with persistence - Lenovo Thinkpad - Synaptics

hi everyone, I'm new here, pls. be tolerant if not perfectly adapted,

since some releases I experience that Lenovo P70 touchpad, pointer stick, and external usb mouse:
DO work with 'live stick', but
DO NOT work once using 'persistence' or 'encrypted persistence',
I searched and found plenty of similar reports about installed versions having trouble after
upgrade, but couldn't test the hints there ( modprobe -r psmouse, sudo apt-get install xserver-xorg-input-synaptics )
because I couldn't manage to open a terminal - even any program - without working pointer.
Anybody a hint to solve without building individual images.
AFAIK the input devices are some flavour of synaptics.
TIA for any help.

3 weeks and no solution? :-(
found some sort of workaround there:
https://ways2hack.com/mouse-not-work...-linux-ubuntu/ there:
https://forums.kali.org/showthread.p...g-issue-Solved and there:
https://forums.kali.org/archive/index.php/t-221.html
seems to be stable in persistence,
on new installs care to fire this first. else if you configure anything
for mouse / touchpad you may get stuck without after restart,
and have difficulties to reach a terminal ... sometimes external mouse may
help if plugged in before! boot.
Would be nice if the ISO can be adapted / repaired,
ver. prior 2021-4 didn't have this issue.