Just now I started my Poser 7 and at once loaded this frogman model and moved him, and his rebreather's canister and blowoff valve did not move with him. So, I selected the canister, and by clicking the parameter dial and typing I changed its yRotate from 0.000 to 0.001 - and his canister and blowoff flew to their correct places. Then I changed the yRotate back to 0 : OK.

If I select his hip and call "drop to floor", the canister and blowoff move correctly with him.

I moved him, and his blowoff and canister did not move with him, and then I called "drop to floor", and he dropped to floor, and his canister and blowoff flew to their correct places.

Earlier, much looking through his .CR2 file with a text editor found nothing wrong.

(These three look ready to sort out the culprit next time he goes swimming or boating.)