Help with radium smart wallet

I wanted to participate in an airdrop yesterday, but I couldn't because it required the installation of the radium smart wallet. I didn't manage to install Radium Smart wallet because the message "Error Loading block database" without further instructions. I downloaded the core and smart chain directly from https://radiumcore.org. When executing the smart chain, it took quite some time to download the blockchain, so it look like something was downloaded, but the error indicates different. I tried it several times on a desktop computer running windows 10, but with no result. I found some FAQ for radium, but very little trouble shooting. It's probably a silly question, but does anyone have an idea what the problem could be?