VPN SSL with AD password renewal - CA setting question

Hi all,

I have some doubts regarding this topic, so, any help will be appreciated.  We have a SSL VPN with AD authentication running on a 60E configured with LDAP, this is working fine but now we have to configure the password renewal setting so when the  active directory user password expires the user can change it by using forticlient when connects to the VPN. So, as far as I was reading for this to work you need LDAPS no just LDAP. But for LDAPS, you need a certificate, and for the certificate you need a CA. So, I was reading about deploying/configuring the CA role in our AD server ("how to") from Microsoft site, and then the doubt came to me since  I don't know if t there's a particular setting for Fortinet about this or the default settings as mentioned here will work:

On the Cryptography for CA page, keep the default settings for CSP (RSA#Microsoft Software Key Storage Provider) and hash algorithm (SHA2), and determine the best key character length for your deployment. Large key character lengths provide optimal security; however, they can impact server performance and might not be compatible with legacy applications. It is recommended that you keep the default setting of 2048. Click Next.

Thanks in advance!