Display informative purchase completion message

Hello, Vanessa!

request addition info from the user such as a telephone number (easier to contact the buyer)

Look at commerce_buy_one_click_phone.zip archive attached to this message.
This archive contains commerce_buy_one_click_phone module.
I use this module in my shops to add ability for the buyer to enter his phone number in 1-Click form.

To use this module, you need do the following things:
1. Install masked_input module: https://www.drupal.org/project/masked_input
And place maskedinput folder from my archive to libraries folder. (my archive contains maskedinput 1.3.1, it is much better than laggy outdated 1.3 which is provided by default)

2. You must add field_name and field_phone to the billing info of the user.

In other words, you must go to this page /admin/commerce/customer-profiles/types/billing/fields
And add two fields of type text with field_name and field_phone names.

3. After that "Buy now with one click" popup must contain "Your phone" field. (see attached screenshot)
You can change mask of this field in commerce_buy_one_click_phone.js file.

4. You can make "Your email" field not required on /admin/config/commerce_buy_one_click page.

By the way, you can also look at code of commerce_buy_one_click_phone module and easly change it and add other additional fields like phone to "Buy now with 1-Click" form.

Provide a message to the buyer with a link to the sellers page (the user who created the product)

I need more info.
What is "the sellers page"?
Are products created by users (not admin) in your shop?
Do you need to change the final message which is shown in popup when user data is successfully submitted? (Your order was successfully created ...)

I just have pushed new DEV version of the module.
This dev version contains new hook: hook_commerce_buy_one_click_order_completed_final_message_alter.

/**
 * Implements hook_commerce_buy_one_click_order_completed_final_message_alter().
 */
function hook_commerce_buy_one_click_order_completed_final_message_alter(&$final_message, $order, $order_user, $form_state) {
  $final_message = 'My custom final message!';
}

You can use this hook for altering final message as you wish.

Automatically log in the anonymous user after completing the 1 click purchase (integrate with Commerce Checkout Complete Registration module)

Yes, you are right, this feature in not implemented yet.
Maybe it is possible to do such thing with rules? (I am not sure)
Anyway, I don't use this feature in my shops and don't have enough time at the moment to implement it. (unfortunately)
But if somebody will implement that and share the solution with me (patch or something like this), I will add this to new release of the module.
I will also implement this feature if my clients will ask me for something like this.

Denis

Hi Vanessa!

If you don't want to use masks, you can delete or comment corresponding code from commerce_buy_one_click_phone module. (I think you know this :) )
Anyway, as far as I understood, your problem is fixed at the moment.

Feel free to reopen this issue.

Denis