download the attached file and extract it with right click. then run installer.msi and you are good to go.
Github repo for all the interested
You will see a new option apering at your bar, close to the clock applet, there you can select the keyboard you want to use
If you want to modify it you have the klc file, wich is modifiable with Microsoft keyboard creator
for putting dots on top like in the word iċ, you need to press (AltGr and + in american keyborard), for anyone else (AltGr and [the key two spaces at the left of the backspace]) and the letter you want this is the table of results
for putting a long stick or accent or macron on top of a vowel just press the key + on a american keyboard or two keys at the left of backspace in other keyboards table of results
for the vawel œ̄, you have to press ctrl and the key one space at the right of the l in qwerty keyboars the image is pretty descriptory