Screen slow in calc v6.1

I’ve just upgraded to latest LO but I’m finding the screen in Calc quite slow to update. It is useable but the definite lag is distracting and makes the software harder to use.
In timesheet, start at A3880 and hold ‘up arrow’ key down. Sheet will scroll down. In 30 secs, LO gets to A2990 (around 1800 rows), LO 6 gets to A3660 (i.e around 200 rows). Libre 6 - openCL software interpreter on or off makes little difference.
Environment: LibreOffice Version: (x64). Win 7 SP1 as VirtualBox VM (Win 8.1 host) for both tests. The VM has no access to graphics hardware.
Any suggestions will be welcome, otherwise I will reluctantly regress to Libre 5.4
Regards and thanks
Test file attached, test and results in first sheet

Version: (x64)testHealthLog-181008.ods

Please provide a sample file to test.

Thanks Mike, test file attached to question - different file than one I used for the original question but it shows the problem clearly.