Help Rope stretch problem

[Agony]

Obstacles/colliders in the scene are not affected by substeps. Collision detection is only performed once per frame, regardless of the amount of substeps used. Only constraint solving and integration are performed once per substep, so unless you have extremely long ropes (or many ropes), increasing the amount of substeps should be fine.

Ok, one more question, can I dynamically change the mass of every particle in the rope?