Bug report: Custom Spring Bone does not animate

[saturday06]

Describe the bug

Custom Spring Bone settings in Blender do not animate/move.
VRoid Studio-generated parts in the same file appear to work correctly.

To Reproduce

Steps to reproduce the behavior:

1. Configure Spring Bone manually
2. Play or simulate
3. Custom Spring Bone does not move

Expected behavior

Custom Spring Bone animations should function correctly.

Screenshots

Desktop (please complete the following information)

• OS: Windows11Pro
• Blender: 5.0.0
• Addon Version: 3.17.1

Additional context

This issue is a separated report from the following original issue:

• バグ報告: バグ複数 #1125