Sending Claim Code to Device

Thank @jeiden you for the links and answers.
It's understandable but I wouldn't say that documentation is at "everything you need to know" stage.
Back to the specifics:

  1. Yes, the fact that there is no customer association in devices view and no "Unclaim Device" link should suggest that the device is not claimed. However, I'm unable to claim that same device it with "Permission denied" message. Also same device ID appears in customers view which makes things confusing. From what I read, having the device in possession and performing the claiming process with claim token should override whatever previous ownership was, but it's not working for me. Any help is much appreciated, I can PM device info etc.

  2. Is there a parameter or separate login endpoint for customers of specific organization? Say customer of my organization purchases particle based product from another organization and uses their (same) email to create the new account with that other organization. What is going to happen?

  3. I found the SMTP setup page, thanks. Now with that configured, what needs to be done to initiate the process from the web application? I'm interested in organization specific process if different.

  4. Ok, so with the setup process takes care of claiming and there is no need to claim device at the end. Correct? Now when it comes to previously claimed units, according to this post by @zachary quote:

More importantly, if you have a Photon in your possession, and it is claimed by someone else, you just need to perform setup to claim the device. If you are borrowing the device from a friend, you can claim it from your friend, and then when you give it back, the friend can simply claim it again.

I should be able to claim device eve if it has an owner as long as it is in my possession, yet I'm not getting units reassigned to a new owner in the setup process. Any advice?