Path Of Diablo on Mac - How do i change the gateway?

Hey, after tinkering around for hours, following every available tutorial i just can't figure out how i change the gateway of my 1.13 install of Diablo II + LoD on Mac.

" install 1.13c with wine. change gateway to play.pathofdiablo.com replace patch_d2.mpq run via game.exe success "

I'm at step 2 - can anyone tell me how to change gateway? I'm trying to use Battle.net Gateway Editor but it doesn't find the game and tells me i've to run D2 atleast once which i have done multiple times now.