Did you rename them in the bin directory or your install ie in Program files\darktable\bin. THis is where you need to do it. I did it in my build envirnoment but that was not the solution.
@Underexposed Bill just make a build directory under darktable …you don’t need to go into build just run the script from the dt directory it will handle everything…
My sequence to build each time
cd darktable
git pull
git submodule init
git submodule update
./build.sh
then and the end you will see text that includes the word target…copy and paste that and change the word target to package and it will make an exe installer in the build directory…
So if it seems messed up start again. Delete your darktable and the build folders
reclone the git repo
and then follow the instructions above…if your compiling environment and dependencies are all set up then you should be good to go…
Did you run the script from inside build?? It is meant to be run from the darktable directory …it handles all those other commands that are listed in the build directory…
?
Okay so that will update all the commits…now do the two commands for submodules init and update and then try to run the script to build
./build.sh
Congratulations, you’ve just been bitten by “don’t ever use spaces in directories and file names”! For comfort, you’re far from the first or the last person to do so. 
Windows assigns the user name, so I am stuck with it. I used quote marks, but I guess that’s not good enough. How do you get around it?
Again, ran into same
Unknown argument Martz/darktable/build
It merely suggests it. You’re the one who clicks “Next” to perform the actual assignment, no?
You could e.g. create C:\msys64\home\foobar and drag the entire darktable folder to it. Then in your MINGW64 console, you do cd /home/foobar/darktable or cd /home/foobar/darktable/build depending on your approach and continue from there…
How would I know, I have no memory. 
I’ll try rearranging the furniture.
Can you not just rename and add an underscore??
Too simple. Ha!
On my way.
Rename it Bill_Martz, but when I opened mingw64:
If that messes it up you can still cd into your build dir and follow the manual commands…just as in build.txt
No, because his Windows username maps to his MSYS/MINGW64 username and that home directory must be present (for various config files, etc.).
There is of course a way to handle-remap this, but let’s not make things more complicated, seems like there are enough hurdles as is…
So, rearrange the furniture?
You can go to your original setup. You would need to modify the first line of the script that sets the directory and it might work…but maybe just abandon the script. and use the commands in the build txt file just paste them on the command line after changing to your build dir
Finally build and install darktable:
mkdir build
cd build
cmake -G "MSYS Makefiles" -DCMAKE_BUILD_TYPE=Release -DCMAKE_INSTALL_PREFIX=/opt/darktable ../.
cmake --build .
$ cmake --build . --package install
Shows funny when pasted here but basically what is shown in the build.txt instructions file…just note the change to package from target
Move everything in
C:\msys64\home\Bill_Martz\
back into
C:\msys64\home\Bill Martz\
and then follow the original instructions. Yes?
That should work. If you look in the script you can see where the issue is. Its a text file so you can easily read it…the directory is set by dirname and the space messes with it. You likely could hardcode your directory path in there and the script should run but maybe just go line by line for now from the build instructions to get it to work the first time…