[thanh019]

Since you have attached the imported .tap program to the base of the robot, the imported trajectory moves with the robot base attached to the ext axis. If you use a static frame (not attached to the ext. axis), this allows you to adjust the position of the robot base relative to the imported path. In the opposite case, it is not possible to maintain the tool orientation as part of the path is unreachable.

I have attached a modified station. Frame 3 is attached to the base frame of the station.

I really apologize that it takes some time for me to think and try your instructions. I am not sure I perfectly understand your idea but I did try to make a curve follow project instead (it is Path 5 Settings in the attached simulation), inspiring from your "box curve following" example previously. However, I do not know why the approaching angle of my project is so weird, it is very inclined and I do not know how to set it back to vertical orientation. Moreover, I cannot control how the tool turns as the robot arm suddenly "sinks" and keeps a confusing orientation on the short side of the workpiece.
Please help me with this as I am so struggling with this but it is almost the final step in the simulation. Thank you very much sincerely.