Hi Christopher, Chimera does not correctly handle more than one transparent model. If you have two transparent models the one with the higher model id number is rendered second and always appears in front of the one with lower model id number. The reason you observed different behaviour (sometimes looks ok, sometimes wrong) is because it depends on the model id numbers. If the transparent model in front has the higher id number then it looks ok, otherwise it looks wrong. Opaque models use the OpenGL depth buffer and do not have this problem. We will need to look into the memory leak (memory is not released when closing a session). What version of Chimera, 1.2352? The crash on Windows is very likely caused by running out of memory when rendering the image. Capturing a full screen image with supersampling (made 3x larger in both dimensions = 9x more pixels) can take significant memory (10 - 100 Mbytes). A machine with 1 Gbyte of memory is barely adequate for displaying ribosome structures (~100,000 atoms) and large density maps using Chimera. My Mac machines have 1.5 Gbytes and 2 Gbytes and I seldom work with atomic models as large as yours. Many EM Chimera users I work with use machines with at least 3 Gbytes of memory. I'll submit a Chimera bug report suggesting we look for the large memory allocations done during image saving and try to change the code to catch those allocation failures and avoid crashing. I don't have a clear picture of the occluded icons problem you observe with Chimera displaying full screen on your new Linux machine. Could you send a snapshot of that? Tom