I have replaced upload.php in 3.6.7 with the base64 upload.php but I still can't upload the settings from a 3.4.9 install.

Any thoughts on that?

Thanks!

did you read the on screen documentation?
you only need to re-import settings if you are transferring them from one site to another or using them as a backup so you can play with some new changes and restore to before your playing.

Yes, sorry this is for transferring from one old site that has not been upgraded to another new site.

I was able to import the settings to a site that I created a few days ago using 3.6.4 after I swapped the upload.php file but its not working in 3.6.7.