Login isn't working, I think it's a bug in the plugin Options

[PartDigital]

Ok so I'm having a problem getting the IPBWI login to work.

Here's what I'm doing.

On the remote Server:

I've set the board cookie settings to look like this:

Cookie Domain: .mmorpguides.com
Cookie Name Prefix: forum

I'm trying to allow users to sign in here:

http://www.mmorpguides.com/

The desired result:
What is supposed to happen is that if it works correctly the form goes away and is replaced by a welcome message.

What actually happens
When the users logs in the form goes away and is replaced by the welcome message.
However, when the page gets reloaded, or if the user goes to any other page they don't stay logged in.

On the local Server:
On my local server I'm running the same version of the forum but I get slightly different behavior.

When I leave cookie name prefix blank it all works perfectly.

However, when I add a prefix (like "forum") I get the same behavior that I described above.

I think it's a bug
I'm positive I've set up everything correctly (since it does work without the prefix) so I suspect that there's a bug in the plugin.

did you guys have any thoughts?