when i click the Translations... button, i just get the popup error (see attached image - "An error has occurred! Object reference not set to an instance of an object.") - with or without the json files present

what is going wrong?

FYI i have MKVToolNix GUI v98.0 installed

DotNetVersions reports this info for my W11 Home (25H2 Build 26200.8457) x64 system:

C:\Users\User\Desktop\DotNetVersions>DotNetVersions.exe
Currently installed "classic" .NET Versions in the system:
2.0.50727.4927 Service Pack 2
3.0.30729.4926 Service Pack 2
3.5.30729.4926 Service Pack 1
4.0.0.0
4.8.09221