if I want to do the multi-quote in a thread, I click the (+), click the second (+), and then click the (quote) button, and only the post where the (quote) button shows up.
Yeah I'm well aware. With the latest vbulletin release Im finding a few things that we're behind on (multiquote for example). I will be reworking a good bit of things soon. Sorry for the inconvenience.
I use Opera and copy/paste with the back button(which is simply hitting the "z" key or hold down right mouse button+click the left at the same time) seems to be easy enough
If it were to be working the way to properly use it is to select the threads you wish to quote and then hit the post reply button.