Version 4.1.48 is a recommended download as it fixes a bug introduced a few weeks ago whereby paths with variable extensions were being converted into truncated paths. This obviously caused problems with data that was subsequently streamed out via GDS2/OASIS.
Various bugfixes have been made to the 'Compare Cells' command and it is running very well now on multi-cpu machines. In fact this is what picked up the bug above, when two (supposedly identical) chips were compared, one which was the stream out of the other.