In this case you will need to contact your system manufacturer for better assistance as they are more familiar with your system configuration and how all the components interact with each other.
Your system manufacturer is As Rock, you can see it here:
NOTE: This link is being offered for your convenience and should not be viewed as an endorsement by Intel of the content, products, or services offered there.
Many thanks for taking the time to reply.
However, I think I have now answered my own question.
For me, 32gb is just too small for Windows 10, even if apps are installed on a different drive.
Therefore I have ordered a mSATA drive and when it comes will clone the 32gb c drive. Hopefully I will be able to simply change the initial boot drive in the bios (or whatever bios is called now).
Just to close this thread, I added the 250GB mSTAT drive to the N1350 and cloned the 32GB mmc to the mSATA then adjusted the boot priority to use the mSATA.
I was worried that having two full Windows 10 OS drives in the same PC at the same time might cause problems but so far all is well.
There is no noticeable speed difference, but I can now loads lots of Apps without worrying about capacity (at least for a while :-))