Lightroom 4.1 and Photoshop CS6
1. Photoshop freezes after opening mulitple images as layers in one image from Lightroom. This began happening after I updated to current versions of each program, but not immediately after. Took maybe a month or two after updating before it started happening. If I click on another program to bring it to the foreground and then click on Photoshop to bring it back to the foreground, Photoshop starts working again. This was happening when using Lightroom 4.1 and ACR 7.1. I have updated to LR 4.2RC and ACR 7.2RC and the problem is still happening. Nothing has changed with the hardware and I can't recall adding any software or plugins during this time. Could this be a problem with the way I have Photoshop set up? Or, could it actually be related to Lightroom? I only open images in Photoshop out of Lightroom.
2. After working with Photoshop heavily for several hours, certain brushes or selection tools become very unresponsive, that is, the brush tool itself and and the Lasso and Magic Wand. They don't cause a freeze, but take a very long time to work. If I close Photoshop and reopen, it is my recollection that this unresponsiveness always goes away. I assume this is a memory issue and wonder if there is a way to set up Photoshop so this doesn't happen.
I have 8GB RAM installed on a 3 year old iMac. Image files are on external Firewire drives. LR Catalog is on the internal drive.
Have you tried to create a new user account and then test Photoshop or Lightroom from that newly created user account?