I performed a custom include/exclude search. When the results were returned, I checked the first record and the radio button '1 selected records only' was properly chosen. I selected a second record and it worked as well. I went to the next page and selected a third record and it worked as well.
I then performed the search again. This time, before selecting any records, I sorted by contact type. Again, I was able to select individual records. I then sorted by contact type again (to change the order) and when individual records were selected, the radio button showed '0 selected records only' and the action menu was disabled.
I saw this error in 4.6.3 and updated to 4.6.8 and the bug persists.
If this is not the right forum for bug reports, please direct em to the proper venue.