Sitewide use of VB permissions

[MkJnr]

Had a quick browse round these forums and what I gather is that to use the VB member permissions etc throughout your site you would just have to include external.php into your page. Do you then have to write your own queries to use that or is there a way to access the existing functions?

e.g. How would you check that someone is in the usergroup which is allowed to access a certain page? Or could you allow someone to login from a non forum page?

Thanks in advance,

Mark