Hello sir,
we have gone through the reference link as well your description, and would like to inform that, as mentioned we can use the reference link for design inspiration, well we can provide much better design than that, i can show you my portfolio.. For 256-bit encryption you will need to install / configure ssl certificate and for receiving donation, will you be using paypal account ?
Regarding the track conversions from newsletter and all, well this features of email marketing applications like mailchimp, it has nothing to do with the website of yours, you can easily send newsletter and also try down the complete report from your mailchimp account.
we would like to invite you for a quick discussion so that we can explain all the features to you, as well understand your points of requirement.
Looking forward to your valued response.
Regards,
OK Team