It's very simple:
I have a PS3IR-1000 from Schmart as an IR adaptor attached to the PS3. I have a USB UIRT attached to the PC. There is a PS3IR-1000 device template in the main database with the necessary remote codes, I had to add ones for the four Circle, Square, Triangle, X Buttons (which are specified in the PS3IR-1000's PDF manual.), and create a remote for it in HA Designer (I wanted one that wasn't the default DVD/Blu-Ray remote, with the 4 buttons mentioned above), afterwards, after making the necessary changes above (And adding the remote in the device template), I was able to add the AV device using the setup wizard, and it created a scenario for my PS3, and was able to control the PS3 appropriately.