This is not clear. Please give exact steps of what you are trying to do.
Again this is not clear, but my guess is that you are “closing” the Audacity project when there is only one project open. This leaves Audacity still running, so Audacity opens a new project window. This behaviour may look a little unusual on a Mac due to Mac’s weird habit of leaving programs running in the background when the user tells a program to close.
If you wish to shut down Audacity completely, select “Exit” from the file menu (probably “Command + Q”, but I’m not able to test at the moment).
Many thanks for putting me in the right direction.
In fact, my problems are (as it turns out) just a n00bs misstakes - sorry about that.
I have spent all day converting whole albums into seperate tracks with great success i might add.
Strange though that i can open mp3 albums/tracks but not export - oh well, maybe i will get on better with the upgraded version os Audacity.