Thanks for the guidance!
BTW, I have a little problem: It seems that at the moment i'm not able to sell HERO at BTS DEX. There is a text "The owner of HERO has disabled trading in this market". So If I borrow HERO, I can't short it onwards right away. "Settle" command seems to be working but i'm not eager to wait 24 hours until settling will be finished. I'm using light wallet (BTS Munich) - what is it that I do not understand? Thank you very much in advance!