Clean install on a scrubbed disc (deleted the previous version before I installed, too). Installed 5.0.5 update before running it. Selection is basically "stuck." Defaults to grabbing the first thing selected. If I hold down either the brush selector or the lasso selector OR the marquee selector (for a while!), changes behavior to be more like a brush. The lasso does make nifty little shapes if started off the object, but once the cursor is inside it simply selects whatever face or line I pass over. The only way out of this mode is to switch to rotate, scale, or another mode, then switch back. There is a "stutter" and a slight delay during this. This alone makes the software extremely difficult to use. If nothing else, is is no longer possible to marquee around several closely-set vertices to weld them together. The brush selection is nice to have but it seems a terrible waste to have four ways to get at the same behavior and a long work-around to get out of it. Delete key is actually starting to make sense. It acts like the cut tool when used on a vertex or line (that is, the geometry is reconstructed around the gap). It deletes an entire object if that is selected. On a filled poly it does nothing at all. Selecting "Cut" from the menu operates the way delete used to.....after a very long pause. Still, I'd call this a feature, not a bug. On editing chores I was unable to generate the error boxes, although I did find inconsistency on whether the control-key sequence for link would work or fail (had to use the buttons to select the link tool several times to sucessfully link two verts.) The polygon name bug definitely there after re-install. I created a cube and a sphere from the drop-down. Selected each in turn and did "Name polygons." After checking to see that they were selectable by name, deleted the cube. Now it is no longer possible to select by polygon; there are no named groups any more (the sphere group is now nameless again). Created a cube and one step at a time smoothed and converted. At 6144 polys Carrara got rather slow. This is within bounds of reason. At the next 2x multiplier delays of up to ten seconds were encountered on simple commands such as "select all." Also made some attempts to understand fresnel term; so far, I can not find it ever acting to change a material on angle with the camera. At least, not as much as can be seen on a test sphere. In general the fresnel term for reflection was similar to "how much reflection" only it tended to be more like "make the reflection brighter over the whole object." And again, with a fresnel term in transparency, transparency could not be achieved. Oh, and although the index of refraction box value never changed, it is obvious the drop-down does change the value. This is a pity, because actual fresnel behavior is so key in getting glass, water, many reflective objects looking correctly (our own Moon shows a marked edge lightening effect during full moon as a result of shadow-hiding). As far as five days of working with water renders can show, though, the new Carrara fresnel functions do not do this usefully on a Mac install. All in all, my particular install of the C 5.0.5 pro, on OS 10.2.8, acts a lot more like a beta than like a properly patched program. Color me still strongly tempted to re-install Carrara 4 so I can get some actual work done.