[asheshouse]

You need the latest Aircraft Installer v3.8 --- Maybe you have Universal Installer v1.1. This is not the same thing.
Install the latest Aircraft Installer after you install UI 1.1.
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This has various options depending on whether you installed UI 1.1 or one of the earlier mod options.

Best to install beta mods manually if you know how.
Extract Ranwers files to a temp folder on desktop and look to see what you've got.

In the technical section there is an excellent guide by Cirx
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and in case it doesn't work first time
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