Windows 10 doesn’t deal well with older programs, or when changing displays from High-DPI to Low-DPI (or vice-versa). The Windows 10 “Creators Update” will hopefully fix that, but in the meantime, this YouTube video might help out.
In a Nutshell:
- Download this “External Scaling” zip file (or the files individually linked to by the video)
- Open Zip file and extract the registry patch and manifest file
- Run the registry patch
- Copy the manifest file into the same directory as the program whose scaling isn’t working properly.
- Rename the manifest file to “<program>.exe.manifest” where <program> must match exactly the name of the executable.
- For example, for Kerbal Space Program, copy the manifest file into the KSP game directory and rename it to : “KSP_x64.exe.manifest”
- Restart the program.