I was able to get Csound running using jack server. First I started jack server (as described here). Then I started CsoundQt, in its configuration, changed it to use jack audio implementation. For some Csound examples I had to change the '-b' and '-B' values in order to make them to run. For example when trying to run 'Chowning-Stria.csd' I was getting:
*** rtjack: period size (-b) must be an integer multiple of ksmps
ksmps was set to '10' in the patch, so I had to change the '-b' value in configuration from 1024 to 1000, so it divides without a fraction from 'ksmps' value. Then the patch started fine.
To get Csound install, I did:
sudo apt-get install csound qutecsound
Let us know what messages you are getting or what steps can we take to reproduce the issue, so we can help you out getting Csound to run.
p.s. The button could be reprogrammed to start Csound patches instead, by modifying the /usr/local/etc/pisound/click.sh