What seems at face value a rather basic operation is actually a lot more complex potentially. Rather than trying to executing a mass extrusion process do a sample extrusion to see what kind of geometry is output. A planar n-gon with 6 entities will result in 22 entities when extruded. Imagine if those 740 groups have ~100 entities each then you are asking Sketchup to create ~300k entities. SketchUp then has to consider other things like its inbuilt tolerance, are there curves etc.... This is not a simple as a simple extrusion if the geometry you are extruding is not efficient.

@akynxs said: @tig said: Your English is much better than my Portuguese ! I see your settings etc. Most look OK - except the following... My are different to yours... Can you try mine ?? Unfortunately it did not solve. ;( I will remove all sketchup, folders and the registry and do an installation from scratch. I suspect the problem started when I installed Enscape. That's exactly what happened to me, as soon I removed enscape it magically started working again, no need to reinstall sketchup.