Had some issues with my driver's licence at the rental counter, but the customer support agent explained everything and I finally got my car. It turned out that it must be in Latin alphabet, and if not - the rental agency may refuse to give me my car!.I was shocked at first, I didn't want to lose my money and my car reservation for almost 2 weeks! But then the staff member suggested providing my IDP, which saved the situation and I finally got what I wanted.
Tip for other renters: check your confirmation voucher (mine was sent to the email), all the documents requirements are listed in it. Wish I knew it earlier!