Sounds like the version 14 doors and windows are not backwards compatible with their version 13 counterparts.
There is a migration library when going from 13 to 14 but not sure if it will be of any use going back the other way.
I am not sure of this as I don't use the standard library parts and I have rarely had to save back to 13.
I can see 3 options for you if you can't get the libraries to swap over properly.
In your 13 template delete the offending parts and replace them with ones that work. But this will mean you still have the problem on your 14 machine if you need to save it back again.
So option 2 I would open the file in 14 on your machine but swap the library for the version 13 one. Then fix the problem parts.
Now when you save it back to 13 the library should be fine.
The third option is to upgrade all of your students' amchines to verson 14.
Barry.
One of the forum moderators.
Versions 6.5 to 27
i7-10700 @ 2.9Ghz, 32GB ram, GeForce RTX 2060 (6GB), Windows 10
Lenovo Thinkpad - i7-1270P 2.20 GHz, 32GB RAM, Nvidia T550, Windows 11