Hi anderw,
A blank screen can be an indication of a potential browser issue that is preventing the system from displaying the screen correctly. Whilst I have not heard any news of a import time-sheets issues today, I would encourage you to click here for work arounds concerning clearing cache and cookies to fix browser issues within KeyPay and Quickbooks. If this does not work I would then ask kindly for you to give us a call on 1800 046 038 (8:30 - 6:30pm, Mon-Thurs AEST) so our customer success team can have a look.
Thanks,
-Steven