Not sure why this isn't working for me... I downloaded Testbenchcontrols_2.1.20.zip and extracted the contents to my scenarios folder, unselected all mods except for base. Then went to Single player, New Game and under User Scenarios, selected Testbenchcontrols_2.1.20 and hit Next. A map generator window comes up, but I don't make any changes and click play. A default map is generated (which I don't believe is supposed to happen?) and I can't seem to find a 'rail' or 'X' button with or without a blueprint in hand. Any help is appreciated. I am on the latest Factorio 2.55 stable.

Silly me, I tried downloading directly from here and manually installing it and somehow got it under user scenarios instead of mod scenarios. I realize now the in game mod manager knows better than me and is so much easier. :)

Sounds good:)