well, I'd need to see the TerraCustom\Logs\client.log file from the first attempt. That sounds like what is described in the install instructions.It tries to launch, but immediately fails. It seems it still can't find the file path. this is the error I get:
Terraria: Error (tModLoader v0.11.8.1)
Terraria Content folder not found. Make sure to install TerraCustom in a folder next to the Terraria install directory as described in the ReadMe.txt.
I've tried putting the Terracustom folder in the Applications folder next to the terraria folder as instructed and nothing
Tried putting it inside the Terraria folder next to the app
Tried putting it inside the MACOS folder inside the terraria app
I also tried taking the Terracustom app out of the folder and putting it in all the same locations, still gets the same error.
In order to even see the above error I have to open the Terracustom app and launch the unix executable from the terminal, otherwise the icon just bounces then stops and get nothing.
My next step I think is to take everything out of the Terracustom/macos and drop it into the same Terraria folder and overwrite all the duplicate files.