It depends on the program. First step load the program and then go to Project and go to device selection and change the chip to the new Psoc device and click ok. Then you can proceed with debug.
@bob No chance to open the PSoC1 project in Creator. Copy and paste will work for the pure code, but the components are totally different.
You will have to redesign the project for PSoC3/5. Hence, it will be difficult for medium size to large size projects.