Migration of some files breaks Installtool
I get following message in Installtool (Migrate tt_content.image, page.media):
The system detected a fatal error during script execution and redirected to this module.
90% of our files were moved (rename) to the new location. The rest is still in /uploads/pics/. After debugging it seems that this line breaks:
$file = $this->storage->getFile($fieldConfiguration['targetPath'] . $item);
I don't know why because you have a check on $sourcePath above which continues loop on error. After catching for \Exception on this line and set $file to NULL on error, the migration script works again. But in my opinion it seems the error is elsewhere.