Need filters…

Hello,

I am trying to figure out if I can use this plugin (and purchase it). However, to do so I need to integrate a few things into it. For that I need a few filters. Here are my needs:

1) Integration with Kickbox.io. I see that there is a filter ‘newsletter_user_subscribe’ where I can set the status of the user to ‘E’ for error if kickbox.io says it is not a good address. But ideally I would like something that allows me to verify the user without actually saving bad information and cluttering up my database. Is there a WP validate filter for subscribe functions that on failure does NOT save?

2) There looks to be a title/message filter I can use for my newsletters are ‘newsletter_message_html’ and ‘newsletter_message_subject’. This way I can in effect write my own newsletters with my own information as I cannot use just posts, but need to include 3 items from my site. Is this also the correct filters? Or is there a better approach?

Thank you,
Edward Haletky