How can I stay logged in?

I know I should really post this elsewhere, but I always come to this page and I find the navigation a little confusing here to find the relevant topic page. Anyway, if I'm on here awhile I suddenly get logged out for some reason. Can the admin or anyone tell me how to stay logged in for a few minutes/hours/days/weeks/years/decades/aeons? Also a little problem with logging in to 'reply to topic' box. When I do log in accordingly to reply, I'm taken away from the main discussion board back to the homepage and then I have to find 'discussions' to get to the board and thence to the post to which I want to reply to - a long way about it surely agree there? Anyone else finding this problem. Other than that, this is for me the best source for 'Prometheus' info with intelligent discussion and people and a site I'm coming back to more and more often. Edit: when I posted this message, again I was taken back to the homepage instead of back to the thread, so I had to click back on 'discussions' again. What a I doing wrong anyone?