Sounds like the same problem as my previous reply to do with an incorrect address/port or a firewall. You can also double check the value of secure is correct (either SSL or TLS) in the file core/email.php
The only forms currently available are part of the Forms module: https://namelessmc.com/resources/resource/43-forms-module-for-200-pr7/
To create something custom you'd need to create a new module, currently there's no documentation on doing this. You can find an example module here: https://namelessmc.com/resources/resource/115-example-module--documentation-in-es-and-en/ (paid) and here: https://namelessmc.com/resources/resource/29-example-module/ (free)
Your web server does not support friendly URLs - for now you can change friendly from true to false in the file core/config.php
If you are using a web host, create a new file named .htaccess in public_html (or wherever Nameless is installed) and paste these rules inside. If you are using a VPS/dedicated server, there is info here on configuring your server, just note the .htaccess linked is the old v1 version and you should use the one I have linked above.
There is an example nginx config available with some sample location blocks to add to/replace inside your config.