I found out that I'd forgot to change the main class in the plugin.yml file, resulting in a bunch of bugs occurring. I thought everything worked as it should, but apparently it didn't.

Well, that made me spend 2 days on fixing bugs, which is probably good enough, because I can now with safely say that HyperCurrencies is 100% stable.

Java notice: Currency#currencyExists is no longer depricated, due to a fix.

Take a look at the full changelog here