@mrmazda @Bill_L hasn’t re-installed Leap yet…
@Bill_L so in the expert partitioner you need to use the option ‘use existing partitions’ then select /dev/sda1 as a mount point /boot/efi and make sure the DON’T FORMAT radio button is checked. It will complain about the partition being too small, you can ignore this warning 100MB will be fine. Then select /dev/sdc5 for Leap.
FWIW, when I do a fresh re-install of my system, I always start by using a live image distro (typically Mint/Cinnamon) and use gparted to blow away the drive, leaving it with only a fresh GPT partition table.
Then, I do the Windows install and after rebooting to the desktop in my freshly-generated user account, and then I use Disk Management to shrink the C: partition by half, leaving ~500GB for everything having to do with Windows (C: + the recovery partition) and then I’ll reboot from the flash drive with whichever distro I’m going to install, and let it do its thing.
I really don’t like having to troubleshoot and fix avoidable problems.
Users may use the Windows Installer to delete existing partitions.
Yep.
Windows Installer is easily confused by multiple drives. If so users may want to temporarily detach all drives but the one they are trying to install on.
I don’t have that option. TL;DR, HP tech support sent me a Microsoft-branded W10 Home read-only USB flash drive (which obviously is customized for HP) and the only thing it lets me do is set up Windows from scratch.
Honestly, I don’t think I’d use that capability even if it were available to me because I have a LOT more faith in gparted. Back when I was using a 2010 MacBook Pro, which ultimately I set up with Linux Mint, I used gparted, and that’s with me having some degree of faith in Apple’s own Disk Utility. 
Win 10 installed with its standard partitions. EFI, MS reserved, C: , WinRE.
Before I shrink the C: partition, can I delete the WinRE partition?
It is always last in any PM I have used. I have read it ‘can’ be deleted, but recommended to keep it.
Thoughts? Before I get to putting Leap on again?
Thanks for the responses.
@Bill_L I delete them, it will adjust it’s c: directory AFAIK to create a new one if needed.
In the partition layout, it precedes the C: partition, so there’s really little point in bothering.
I shrink C: to 50% and leave it at that.
Why would you want to delete this partition? What are the ramifications of doing so? The extra partitions created during Windows install occupy a tiny fraction of total space available.
What you really need to do is shrinking the system partition /dev/sda3. Boot into Windows, shrink the partition, disable fast startup and quit from Windows:
Finally up and running. Grub2 menus is right. searching for sauerlands wifi dongle info somewhere in past PM’s.
I absolutely hate that glaring white installer.
Every Windows install I have made(XP,Win7, Win10) the WinRE partition has been at behind C: partition.