Please look at the enclosed attachment enlarged screen shot. Look at the normal spaces between the words, in this case real names, and then compare to the non-breaking spaces added between the names "Trevor Horn; Boris Blank; and Tan Dun". Clearly you can see that these NBS are noticeably wider.
This problem exists within Publisher (the latest beta 238) and the previous version too. This problem was identified from viewing an exported 300dpi pdf.
Thank you.