Zero Touch with Mikrotik (Non-Radius Setup)

We have searched throughout the forums regarding zero touch but many seem to use a radius server. We would prefer not to use radius for this and would like to pull our zero touch configs directly off a tftp server using Option 66 from a Mikrotik router.

At the moment we have a DHCP server running on a Mikrotik router which issues an IP address to the SM once the SM connects to the AP (through ICC). However, once the connection has registered, and the SM receives its correct IP, we are unable to get the SM to pull the configuration file from the tftp server. 

We have a tftp server running on Ubuntu 18.04 and have added Option 66 to the DHCP Options list in the Mikrotik. The tftp server is on a public IP and we have verified it can be accessed. What we are trying to do is see why the SM is not pulling this configuration. Even in the SM and/or AP logs, we do not see the SM even attempting to pull theconfiguration file. 

Mikrotik Option66 example config:
'ftp://user:pass@ipadddress/directory/'

We have also tested this with 'ftp://user:pass@ipadddress/directory/filename.cfg'

If anyone has successfully been able to get this to work without using radius any help would be appreciated.

Thanks,