Hi,
Using Safari or Firefox on the Mac (tried different Macs to ensure it's not a single machine issue) I come across this issue:
Open SMTP log via Mail Security / Mail Manager / Open Mail Manager in New Window / SMTP Log
Default list shows 20 entries per page - only the first page is viewable, same for 50 entries, select >100 entries per page and see multiple pages available.
Pics attached.
Cheers,
Darren