Aww, it's Puddin'!!! How neat that you've been able to see him so many times. Very cool that Steve was able to see him so clearly, even without his glasses. Wouldn't it be cool to lay out some talcum powder on or near the chair he likes so well to see if anything shows up (overnight)? I know those are old tactics, but I've also heard of them working for people... in fact, it had to do with a ghost cat in someone's house!
As for the lights.... those disturbances don't coincide with Puddin' sightings, do they? Or have you noticed? I don't suppose, since Puddin' is near, that it would be too unusual for someone else to tag along, or 'come through', as it were. But I don't know for sure!
Kell