If your server has been installing for 2 hours, please empty your cache and reload the page. Should it still install please contact the support.
If you have rented the server on Nitrado itself it should be the PC version. As far as I know, for example, the xBox version is rented through Microsoft.
With friendly greetings
You can also try a reinstall of the server. Sometimes it gets hosed. Reinstall seems to fix it for some.