I've taken a look at the interaction file you sent me. Basically what's going on is this:
1. Because the arms are so stretched, the location of the spine (and head) is affected by the arm placement [since the character must reach for these targets by bending the spine]. 2. The hands, in turn, are affected by the location of the head, since they are parented to it. 3. That means the target the hands are going for is always changing. Hands move to target -> head's location change -> hands move target change. It becomes a never ending loop where the solver is unable to ever reach its destination.
What you can do to remedy this is to not stretch the arms so much, and also make sure the placement is completely balanced (use mirror tool).
Comments
%appdata%/yiffalicious/interactions/local
1. Because the arms are so stretched, the location of the spine (and head) is affected by the arm placement [since the character must reach for these targets by bending the spine].
2. The hands, in turn, are affected by the location of the head, since they are parented to it.
3. That means the target the hands are going for is always changing. Hands move to target -> head's location change -> hands move target change. It becomes a never ending loop where the solver is unable to ever reach its destination.
What you can do to remedy this is to not stretch the arms so much, and also make sure the placement is completely balanced (use mirror tool).