Hi Rūdolfs,
I merged your patch to github master branch, many thanks for that.
The missing translations are part of the Qt components library. On my Qt4/5 installations I haven't found a Latvian file. LibreCAD uses the compiled versions which comes with the Qt installation packages. The Latvian file should be qt_lv.qm.
The Qt translations on my Linux system are in /usr/share/qt4/translations and on Windows/MinGW in C:\Qt5.1.1\5.1.1\mingw48_32\translations.
If you can't find a qt_lv.qm, you have to search for a qs_*.ts file and translate it.
The qt_*.qm files are not part of the LibreCAD project. On Windows they are added to the installer if present, about the packages for Linux an OSX I don't know what the state is.
Armin
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