hi mapalmros, unfortunately we unable to provide you refund because the payment process is on themeforest (envato). you should ask them about this refund.
also about your server, we also unable to do anything. even for the biggest themes sales will suffer the same issues when encountered something like this.
my suggestion, if you unable to do it on your server, you can install it on your local server. and you can learn how to use it from your local. i usually do it before launch my website on production server.