Do you have link so one can see what is happening?

The directory should be templates, not my_templates. You should then be able to select that custom template from the drop down which appears when you add or edit an autonav block. Also, make sure the directory is /blocks, not /concrete/blocks.

Also pretty sure view.css should be in the blocks route directory e.g. /blocks/autonav. I don't normally bother with view.css. I just put the relevant css in my themes css file.

If you've done all that, there may be a problem with your css. Could you post it?

I can take a look if you send me the custom template (view.css and view.php). Just to make sure everything is correct.

Also webdewd is correct in the path, but you might have just missed one folder when posting the question. Correct path to your custom template should be: 'public_html/blocks/autonav/templates/YOUR_TEMPLATE/'

For more in depth information regarding the autonav, please see jordanlevs blog post here: http://c5blog.jordanlev.com/blog/2012/04/hard-coded-autonav-options...

Jordanlev rewrote the the autonav for 5.6+ so he knows what he is talking about. Make sure you read the comments to the blog post as well.