I think there should be a button so you can just go to the next PM instead of having to go back and click on it, a button would help out alot if you are trying to find a certain Pm.

 

That'd take a separate module installed on top of the forum VBB software. I'll suggest it to the owners, but if you were to hunt down and provide me the info about a module that does what you're talking about, it'd make my case much more compelling.

 

Why don't you just keep the original Inbox open and hold down shift and click on each message to open the message in a new window?

 

That's certainly a simpler solution!