There is a problem in that Windows 10 will always revert to the following IP address and Subnet Mask whenever ICS is enabled:
The RPi will not auto-detect this and sets itself with something like:
Changing the IP & Subnet on the windows machine will not work, because using ICS will over-ride the settings. So a static IP must be set in the RPi, its important to note this should be done in
/etc/dhcpcd.conf add the following:
static domain_name_servers=192.168.137.1 188.8.131.52
setting the static DNS is critical, and adding the Windows 10 host, then the address of a real DNS server.
This then allows you to directly plug the RPi into Ethernet and have internet available via Windows ICS.