Using old files in new versions is generally no problem at all.
Just open them and carry on working, but it means you will be working with you old methods and possibly most making the most of new features.
There is nothing that says you have to update your libraries and attributes.
That is a purely personal choice.
Usually you can migrate the library to the latest version, but there will be some issues with updated objects as Lee said in an earlier post, but if you have the migrated libraries loaded, you should still have all the old objects as well as the new.
The problem arises when you want to copy and paste (or share hotlinks) from an old file into a new file/template.
If the attributes and libraries in those files must be the same, or you are going to run into trouble.
Old attributes will import if the attribute numbers don't match.
Or old attribute will change if the attribute numbers do match, but the actual attribute is different.
There is not much you can do except for manually going through and fixing the changes.
Libraries will be an issue unless you also load the migration libraries.
That should take care of most problems.
If any textures are missing, it means the old file had a library loaded with those textures, that you do not have loaded in you new file.
You just need to find those libraries and load them too.
So the short story is...
Starting a new file in a new version should be no problem.
Starting an old file in a new version should be no problem.
Merging an old file into a new file will be a problem if the attributes don't match.
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Versions 6.5 to 25
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