I am running BOINC under Xubuntu 12.04. I installed it from the Ubuntu repository, as you did. I didn't have any trouble getting to Advanced View. The only oddity I am experiencing is that the menu tabs across the top of the BOINC manager advanced view window are almost completely missing. The only thing that shows is "Fi" from the File menu. That's not a big deal because I can get all the menus by putting my mouse cursor in the right vicinity and then keyboarding Alt-T for Tools, Alt-D for Advanced, etc.

I don't know whether there are similar keystrokes to substitute for the buttons in Simple View, so as to get you to Advanced View. Sorry that I don't want to try going to Simple View to find out, for fear I couldn't get back to Advanced! I wish I remembered how things went the first time I brought up BOINC manager under this OS. It must have come up in Simple View, so I must have been able to get to Advanced from there.

Thanks for the replies! They gave me the idea to look at an older installation I have on Ubuntu 10.10, where I found that Ctrl+Shift+A takes you to Advanced mode, and that works here too.

Ultimately it was my own stupid mistake, basically unfamiliarity with the new UI in Ubuntu 12.04. All of the menu tabs were actually there, it's just that with this new UI, they are found at the top of the screen, even if the active window is not full-screen. I should have already realized that from other apps that I had similar issues with, but it seems that my brain has a really hard time finding an app's menus detached from the top bar of that app, after who knows how many years of always finding them in the top bar.