OK actually… this doesn’t seem to work.
I saved the zip to
Steam Library\steamapps\common\Objects in Space\ObjectsInSpace\mods\testmod, start game, and no change - same old ads.
Also the log file shows this, which seems to confirm it’s not being loaded.
Objects in Space
Build 1.0 (windows)
(c) 2018 Flat Earth Games Pty Ltd
Play began: 2019-03-03 22:54:03
[22:54:03] [GAME]: Loading mods...
[22:54:03] [GAME]: Mods loaded (0).
No launch options, and game being started from desktop shortcut created when installing on Steam.