Your ROOT_URL in app.ini is http://git.osmesh.ru/ but you are visiting http://91.221.70.94:3000/MOS/OpenBoard/src/commit/5b6ed8e51284ec0eee6dbebf5b54efe2300607de/plugins
You should set ROOT_URL correctly, otherwise the web may not work correctly.
If warnings was appeared - dialog with warnings details appeared. Each warning is a separate QTextEdit.
That mechanism is general for UBExportAdaptor and can be simple implemented and used in any import or export adaptor.