Many of us, like me, are running Win10, O 4.8.4 and the Fugawi
plugin using the same charts as you without problem.
I'm not aware of any extended log setting for OCPN itself nor Fugawi
First I assume you have the last version of OCPN 4.8.4 from opencpn
You do use OpenGL I suppose?
Then I'd have tried to clean the raster charts cache: tools->Display->Advanced->...OpenGL-[Options]->Clear Texture Cache
the charts database Tools->Charts-> Force Full Database Rebuild
If crashes still occurs please try to find out if there are any particular chart(s) involved when you perform a chart shift. And, BTW, what exactly do you mean by "Shifting charts", is it when you click a chart bar -or?