Downgrade robot software to a version older than the original

Hi Thibault,
We are experiencing sudden termination of move commands randomly.
See here: Thread crashing in movej
Most often our thread disappears without any reason, while still performing a move. Sometimes the move command does not return at all, making the program freeze.
There are no C4A1 issues any more; here we measured and stress-tested the most time-consuming functions get_inverse_kin, is_within_safety_limits, and get_inverse_kin_has_solution, and added the required amount of sleep() depending on the robot model.