I can't get the screw that holds the opening lever out. Tried bigger screwdrivers, penetrating oils and heat. Could it be reverse threaded? Anyone with experience with these?
That sucks. No experience with that gun. Did you try emailing the factory? Nothing like an explanation in broken English to give you more confidence in what you are doing. This is the guy I would try:
Chief Designer for Small Arms, Sporting and Hunting Weapons
Vladimir P. Budanov
That screw would sure be vulnerable to working loose as the latch is used and released no matter which way it's threaded. I'm wondering if some other piece locks it. Is there any chance it's in a through-hole and has been upset by a punch on the other side to keep it from being removed?