A: Create a simple subscription form with EMAIL field only: https://i.gyazo.com/a2f6e7ddd2c899f891fdd2b301c47b11.png

Then generate HTML code:
https://i.gyazo.com/e4fb8a81f6af60af1070eb50ddfcfda9.png

And copy-paste code from <form> to </form> in LeadPlayer

Let me know if you face any issue. Thanks