One doesn't 'import' a course, per say ... only restore. The term 'import' in Moodle most oft refers to importing the SQL file to a DB - I think.
The max upload is found in php.ini and one needs to set 2 variables as they are related:
; Maximum size of POST data that PHP will accept.
; http://www.php.net/manual/en/ini.core.php#ini.post-max-size
post_max_size = 210M
; Maximum allowed size for uploaded files.
; http://www.php.net/manual/en/ini.core.php#ini.upload-max-filesize
upload_max_filesize = 210M
Values you see above are from a server that is not shared.
Changes to php.ini do require restart of Apache service for changes to take affect. Any course that was installed/created previous to the change will still reflect whatever value it had it settings. To increase in that course, visit the course settings and check the pick list. The highest value should show.
As far as restore failing ... much depends upon what mods/activities, etc. Some (even core mods) had issues with being restored from a backup in version 1.9.x - unforunately, if you have one of those issues, there are no fixes being provided for that version.
When you say 'lessons' ... is that the core mod 'lessons'? Is lessons mod enabled? Some core mods were dis-abled (hidden in 1.9 terminology). Don't re-call if that was the case with Lessons in that version or not. And don't recall if there were backup issues with that mod either ... maybe someone else knows.
To get a clue, check moodledata/temp/backup folder. That folder is used for backups and restores.
'spirit of sharing', Ken