Interesting you suggest the battery may be faulty. I'm unsure how to "condition it properly" (when they installed it I got NO instructions! The other one lasted for years. I had never even seen the icon with the power cord on it! And as I think about it...I did get the new battery before I returned to SL...so you may be spot on. It's not the viewer...it's the battery! Unsure what "redoing thermal paste/pads on CPU" means (off to google that one).
Everyone seems to be in agreement, despite my feelings about it being a viewer issue, it is more likely a recent Hardware issue. I'm so grateful for your patience and advice. I'm taking notes and will bring a LONG list to the apple store!!
Thank you again for such a detailed response. Despite being in SL a very long time, I'm new to this forum (apologies about the "quotation" thing- was unable to sort out how to just repond w/out your statment.
Take care,
Skye