MyraPad is a command line tool to view the xmmp files.

Installation
dotnet tool install --global myraviewer
Update
dotnet tool update --global myraviewer
Running
myraviewer <file.xmmp>
Configuration File
MyraViewer maintains a configuration file (MyraViewer.config) in the "~/.config/" location. It contains various settings such as window size. Delete it if you want to reset the settings.