Hi,
If all thats' provided is a .ldf file, then documentation is what's missing.
That's true. The only documentation is the user manual in Hungarian language: http://www.math.bme.hu/latex/magyarldf-doc.pdf
Does the new file have incompatibilities with the old one?
No. Here is an excerpt from the new one: % magyar.ldf 1.5 is based on magyar.ldf 1.4. However, it has been totally % rewritten and extended (just compare the file sizes), and it doesn't share % code from the earlier versions anymore. However, its default configuration % tries to be compatible with older versions. I didn't get any bug reports about compatibility problems so far. (I've got about 20 reports about other issues. All of them are resolved now.) Best regards, Péter
