Hi, I downloaded and compiled the 1.4.0pre3 version of LyX. When I opened a lyx file, the math macros are loaded empty; with no name nor content. If I save the document, the lyx file will also have empty math macros. A work around is to close the file without saving and reload it.
Just in case you need the information, I work with SUSE Linux 2.6.11 with Qt 3.3.4. And thank you for working for this great software! Best regards, Sami Hanhijärvi