Installing El Capitan in Macbook Air Mid2011

アップデート大変だった。もうやりたくない。
I updated my Macbook Air for developing raw images of α7R2.
Switching my cameras caused a problem on PhotoShop CreativeCloud.
My Macbook Air's OS version was 10.7.5 Lion so the latest PhotoShop hadn't worked.
So I had to renew the OS from Lion to El Capitan.
High Sierra demand PCs have more memory than El Capitan,
therefore El Capitan might be better than High Sierra for my aged PC.

At first El Capitan should be downloaded in App Store managed by Apple.
But I couldn't submit my Apple ID because I hadn't used it at all.
And the latest OS is demanded for submitting new accounts.
To authorize the ID I'd spent a week to search how to do it.
Then I gave up myself and called the support number.
A staff recommended me to make my account valid by Windows PC.
The latest OS is only demanded for OSX but Windows.
Luckily I have a Windows PC too and finally I succeeded to get El Capitan. 

At the same time, Keyremap4, for remapping the keyboard layout 
from JIS to US, gets unavailable due to the update of OSX.
Because Keyremap4 had been developed as Karabiner.

So I had to update Karabiner too.

I should have bought an US typed Macbook Air.
Better or worse, my laptop works pretty well without any problems.
So I can't have another laptop.