I have the SAME PROBLEM, in the past my sketch work. With OS X 10.10.3 I have lost the function or the "Phidget C library".
the error is:
"ExceptionInInitializerError: no phidget21 in java.library.pathCould not locate the Fidget C library.The Mac Phidget21 must be installed."
I have re-installed the DMG and Repair the permission after the update of OS. Testing it from preference work, but in processing not.