Which version are you using - Freelance or Team?
I have installed 7.0 and 7.1 on my machine.
Why both? 7.1 is a replacement of 7.0, to correct some bugs, so why would you need both?
Have you registered the version you're using (Start - Programs - Trados x.x - Register Trados x.x)?
If I create a new TM, these items are available to me from the File menu: Import, Export, Setup, Reorganize. If I close Translator's Workbench and open it up again, those options are no longer available. If I open an already existing TM, they are also not available.
If you're using the Team Edition version, these management functions are only available if you open the TM in Exclusive mode. Did you activate the corresponding checkbox when opening the TM?