Alrighty, I’ve found a solution! (ty to lbraud for idea ;))
In skydome BP construction script, find commented section that says “Set sun’s pitch based on “Default Hour”” (it will be near left side). Then go “Make Rot” node in that section. Set “Roll” input value for node to equal 1 (by default it will be zero).
should eliminate it getting stuck. I don’t know if is right way to fix gimbal lock, or if there’s a better method, but it works 
(If somebody does know a better method, please tell me!)