I have not been able to duplicate the dials not working or the shoulders not working.

Here are the steps I tried.

1. Loaded G2F.
2. Set the Belle 6 morph to 1
3. Saved the scene as a PZ3.
4. Closed Poser.
5. Opened Poser and the saved file.
6. Tested the Belle 6, Kieko 6, Girl 6, Aiko 6, and Aiko 5 morphs. They all worked just. The heads morphed to a proper shape.

I repeated the test with file compression and PMD saving and everything worked. I am I missing a step?

For the shoulder issue,

1. I loaded a G2F applied the i13's Playful Callie6 #23 pose and saved.
2. Then I closed and reopened Poser.
3. Loaded the saved file.
4. Added a new G2F to the scene and applied the i13's Playful Callie6 #23 pose to it.

I noticed the arms did look like your image. But, the saved figure was at a X-Trans of -1 and the new figure was at a X-Trans of 1. When I set the X-Trans of both to 0, the arms were identical. So I am not able to duplicate that issue as well.

DSON Importer does have a cache location. You can see where it is in the Poser menu: Scripts->DSON Support->Import Preferences...

You could try emptying it's cache, but I don't know how it will effect your saved files.