Any ProntoScript contained on firm keys will not work if you are downloading to the remote via PEP v1 and your TSU9600 is running a firmware version higher than v7.1.21. Something to keep in mind. That being said, if your configuration file doesn't contain ProntoScript on the firm keys it certainly wouldn't hurt to run the latest remote and extender firmware. I wouldn't anticipate you'd encounter any issues. If you do you can always revert back to an earlier firmware release. Of course you could also simply open your PEP v1 XCF in PEP v2 temporarily just to download to the remote. Just make sure your PEP v1 XCF doesn't contain any IR codes learned to buttons. PEP v2 only supports database codes. You'll also want to be sure once opening your PEP v1 XCF in PEP v2 that each of your project components in PEP v2 are set to use the appropriate extender and IR port if you are using extenders.