Thanks for the reply, Babgvant.
This is my preferable options for DVRMSToolbox's use:
1) to process recorded DVR-MS files to mark the embedded commercials' start & stop points for ease of playack.
2) to be able to manually load DVR-MS files into the DVRMSToMPEGGUI to convert to MPEG file for commercial deletion & recoding to XVID.
I'm not sure what has changed between versions to prevent this happening as it did with v188.8.131.52. Thanks.
I have tried to comprehend the WIKI to setup a new condition to allow this without much success as I don't really understand the terminology involved.