applyImpulse() along a vector, glitchy simulation

Hello all,
I want to apply impulse force along the direction shown in the picture (yellow arrow), which is a local Z for the object. I found the direction of the application through vector calculation and I am applying force by changing the magnitude of the vector. I am not able to get the results I predicted and they are not reproducible as well. When put a platform under the objects (second picture) the object goes through it. Please help me out. Correct me if I am doing it wrong. I have tried with apply force but it just seems to apply at the center of the object and does not rotate the object also.

Picture 2 - with the chute.

Blender file

test4_scale_10x.blend (892.5 KB)