The lastest Milton version is v1.5.1
You can download the latest Windows (64 bit) installer by clicking here.
If you get a Windows Smartscreen warning, you might have to click "More info" and "Run anyway".
If you are having problems running the installer, you can get a standalone Zip by clicking here.
The release page in github has more detailed in formation.
Milton is free for Windows and Linux, but if you find it valuable and have money, there is a paypal donate link below this paragraph and a patreon link on the right side of the page.