As the others have said you can’t use the 25 library in 24.
You can back save, but the library objects and all of their macros would need to be in the embedded library for that to work.
Any new 25 commands in the objects would stop them from saving back.
However I think you should find that the library objects (or most of them) will migrate back automatically.
Save the file back as 24 an then just swap the 25 library for the 24 one.
it may not be perfect, but I think most objects where possible are scripted to be backwards migrate-able.
One of the forum moderators.
Versions 6.5 to 25
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