I was getting same error, ended changing line 179 in file
export-import-menus\models\DspExportImportModel.php
with
$content = json_decode(file_get_contents(str_replace(WP_CONTENT_URL, WP_CONTENT_DIR, $uploadedfile)));
Thank you very much, ill find a way to bypass it for now.
Hello :),
I can confirm that both are working perfectly, the form is made up of a lot of different fields, and all work. The only one not sending the data properly is the wysiwyg.
