It is not Builder that is having the issue here, but, as the error notes and you yourself conclude, it is an issue with the Psychtoolbox library and your particular system configuration. On Windows and Mac, you can get everything bundled together in the standalone app, but on Linux, you are responsible for handling the dependencies, which may pose issues that are idiosyncratic to your particular setup.
Having said that, if the issue is reproducible and likely to affect others, you should submit a detailed issue report at:
Just uninstall the psychtoolbox package. In its absence, the Keyboard class is smart enough to fall back on the event module automatically:
PsychoPy is an open-source project, created by people volunteering their time because they are passionate about providing software for themselves and others to do good science. You might want to consider that when phrasing assistance requests on this forum, which are, again, responded to largely freely and voluntarily as a service to others.