To be clear: You can select Forward and Reverse on the trans shifter but there is no resulting motion?
Also: You're definitely talking about the neutral screw on the transfer case, not the screw on the transmission. That's what Jean is referring to.
Winding the screw in places the transfer case into a neutral state for towing. Winding it back out when the transfer case is in a neutral state allows high or low range to be selected again. There's nothing in the manual about the transfer case
selector being in 'neutral' before winding the screw in, but the transfer case must be in a neutral state before winding it back out. Screw clockwise until bottomed = neutral. From neutral, screw anti-clockwise until flush = restored operation.
It sounds like you have inadvertently locked out the transfer case selector. I haven't seen any published info on how to deal with that.
You are backing the screw out to a flush position, as per the last warning in the manual?
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