Attached error message is from JGR source.
Anyway I don't see how CMake can't find a file present in source, and I don't see important changes in this area between both JGR revisions, or even between JGR and openttd master.

Oh, attached one was a mistake, BTW error message is same.
I even can't see any important changes between both JGR revisions, but only current master of JGR version builds sucsessfully.

It seems CMake has issues finding our cmake folder. This will be a bit hard to debug for us, as it is possible it is only a local issue (we build Mac builds daily, so we know it should, in theory, work :P). So let us try to gather some information to help you further.

Options is included on line 32 of master, and used on line 33. Those are the two errors you are seeing. Line 22 extends the locations it looks for these files to include the local cmake folder. Could you tell us the output of the following commands (from the git clone root folder; so not inside the build folder):

ls -lh cmake/Options.cmake
find cmake

Next, we need to know a bit what CMake is doing. Could you add above line 22 something like:

message("${CMAKE_SOURCE_DIR}")
The line that follows should be:
set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake")

and rerun cmake .. from your build folder, to let us know the first line CMake gives you back?

That info might help us a bit further along this venture, as a venture it will be! :)

Hmmm.. It's weird.
I have downloaded source again and restarted my computer, it's working propually like others do.

But anyway, message comming from message("${CMAKE_SOURCE_DIR}") is NOT that.
Output was /Users/(my_username)/Downloads/OpenTTD on above line 22, and even below line 22.

(I git cloned on Downloads folder, so Downloads/OpenTTD is a local git repository)

Very odd; but I guess we can call this ticket resolved in that case? :)

If there is anything else we can help with, let us know!

Of course why not? thanks for help :)