Harmony 14 advance and Stage compatibility question

Dear support and fellow artists,
The studio I worked for uses Toon Boom Scan (V 9.2.0) and Stage for production. I am trying to set up a working station at home so I download a free trial for Harmony 14 advance. For testing purpose, I opened 2 scene files created with TB Stage on H14 , made a drawing change (added a couple strokes) in one layer in scene 1, and imported a .PSD file and a .tvg file in scene 2. I brought both files saved under H14 back to my studio workstation and see if I can continue working/editing on TB Stage. However, I got an error message on both scenes telling me I can’t access the layers that I modified under H14, while the rest of the layers that weren’t touched in H14 opened up fine. Like I mentioned, I only made a couple of very simple changes (added a brush stroke and imported a .PSD file and a .tvg file), I assume I did not use any new/advanced capability that I was not able to do with TB Stage. The modified layers simply show nothing on TB Stage.
Can anyone please let me know if I did something wrong or is H14 not backward compatible? Is there a solution? Thank you very much!

You can’t open stuff done in a newer version using the older version of the software.
Even without changing something, once you save the scene, it will be converted to
V14 format and can no longer be opened in V9.2.

Also the difference between V9.2 and V14 is quite large, there have been a lot of
changes made in the software between these versions.

Thank you! Just want to make sure it’s not something I did wrong.