The problem occurs when I create an own Demonstration (New -> Demonstration), add the code
Manipulate[a, {{a, 1}, 0, 2}]
in the Manipulate section, run, save and restart Mathematica.
For the examples from the Wolfram Demonstration Project only some work. Just tried the first one popping up on the webpage ("Quasicrystals" - in the CDF version) and it does not run but produces errors, probably because the Controllers are somehow incorrect initialized.
I tried with Mathematica 9 and 10. My OS is Ubuntu 14.04.
