Thanks for your feedback!
Actually you can download the installation files for your purchased products from your Telerik account/Mange Products by choosing the corresponding product from the list of your purchased products and clicking the Download button/Browse all product files/Manual installation. The .zip file with all the DLLs, skins and scripts will be automatically downloaded to your machine and you will be able to use it for installation as many times as needed.
Please, take a look of the atached example screenshots of my account I made for your convenience.
In case of any further queries, I remain at your disposal.
the Telerik team
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