HelpSecret Login Error

Every time I insert my steam shared secret, it doesn't do anything. Its a steam account so I don't have the option to insert an email and password. If I remember correctly you can leave both of those areas and blank and just enter you're steam secret. This is not the case, every time I enter it, it tells me to fill the email area out. (Not a valid email address.)

Am I missing something here or am I just not using the right steam secret?

(I use Steam Desktop Authentication to find my shared secret)

You need your steam user id too. I don't know what Steam Desktop Authentication is, but you can definitely find it with Fiddler by looking for requests to rotmg and seeing the guid and secret.