OK, I found this closed tracker issue which explained it all:

https://tracker.moodle.org/browse/MDL-25631

To summarise it was previously possible to import without legacy files, but this was really a bug which suited some, but hindered more. So two fixes were made independently. One offered the user the option to opt out of legacy files in the import. The other always brought through legacy files. Ultimately it was decided that the latter was the best option because it applied to restore as well as import, and was a consistent policy.

Anyway following that, I found a solution. Comment out this line 

 $this->add_step(new restore_course_legacy_files_step('legacy_files'));

Around line 74 of /backup/moodle2/restore_course_task.class.php

Then legacy files won't be restored. Just uncomment it when you don't need to kill legacy files anymore.

 

Justin

And an important part of this is the need to make sure that your course does not still depend on legacy files. Otherwise you will cripple it in backup and restore, if you leave legacy files behind.

 I decided it would be easier to write a plugin to copy legacy files into each file area they were required. Easier than doing it all manually that is. It wasn't easier, but if a few other people use it, perhaps it will have been time well spent. 

It is a TinyMCE plugin, called "legacy files go poof." You will need to use it on each html editor/html area you wish to purge legacy files from. (Yup .. you read that right.) You go in, select all or some of the content, and press the "poof" icon. It will copy the files and update the html for you. Then you save the activity as usual. It works best if you turn off legacy files first in course settings. Then you will see the broken links turn into pictures and stuff.

I will try and make a video to make it clearer. But you can get the plugin from:

https://github.com/justinhunt/moodle-tinymce_poof

 

 

Hi Justin

I too hope to solve this problem in two sites. Both are "old" sites originated around Moodle 1.4/1.5, successively upgraded to 1.9.19+. After a couple of failed attempts to upgrade the full sites to 2.2, we decided to take the manual backup/restore path, the target version was finally Moodle 2.4. By that time the opting out of "legacy files" was not possible, so both sites now contain legacy files.

There is no immediate problem, since we do not take "automatic" backups (we take site level backups). In fact the legacy files made the transition easier for most of the teachers and they still have nothing against them. My worry is that because of these legacy files we'll hit the wall in a future upgrade.

I haven't looked into the details, and wanted to say thank you for the work you have done!

As promised here is that screencast of Legacy Files go Poof in action.

http://screenr.com/Ho8N

(Thanks Derek, I voted)