>>"Is there any problem in Bluetooth itself?"
Bluetooth and BLE are standards and trademarks of the Bluetooth SIG. In order to use the name BLE (and many other of the trademarks), the manufacturer is required to list the product on Bluetooth SIG’s website, which does come with a fee. If the trademarked names that belong to the SIG are not used, then there is no need to do this, but the customer should consult with their internal counsel on this as we cannot list all of the terms that are trademarked by SIG. In general, if customers want to market their product as Bluetooth or BLE compatible, then they should need to pay the Listing fees associated ($4k for members; $8K for non-members).
>>"Are there any licensing issues with Windows or OS?"
There won't be any licensing issues from Windows or OS.
Hope this answered your questions !