Try the Windows version, we're running under Parallels.
I seem to remember some funnies with the Mac version. We also had problems because we'd gathered a lot of sessions before looking at them, over 350 of them. Any session above 340 would be corrupted unless the last digit was 1 or 6. Martin at Robo is looking into the cause and will get back.
Apart from the Iphone app this seems to be the only solution. I was going to write a parser myself until I found this.
andy