How can I use and buy a Gunbot license?
PM Gunthar. You need to pay 0.1 BTC or you could use a discount code and pay less:In case that someone is interested in buying Gunbot, send a PM to Gunthar with the referral code "GrumpyKitty" for 10% off. 
You can find guides on the GunBot forum and there's a big telegram group: https://gunthy.org/index.php?board=1.0.