We are aware some customers were briefly experiencing delays when running certain tasks in payroll. We escalated this a short time ago and are happy to advise the issue no longer persists. If you are experiencing a different issue, please feel free to reply with further details on any errors and so on and I'd be happy to assist further.
What I would recommend is that if you are unable to see the Green Finalise button, that you try zoom the page out of the screen. This can done by doing on your Keyboard Control + minus button on ( - ), alternatively you can use the wheel on your mouse to roll back to zoom out.
Try this and let us know how you go when on the finalise payrun screen.