I might be going off topic here compared to the recent discussion but feel this thread is the best place to put this question.

I downloaded the GR2 Converter (LSLib v.1.15.4) and found that it worked fine on older saves, but not on current ones, because of version 5 not supported.

So I got the source files into visual studio and it seems that they changed the compression method to something new. It currently supports ZLib ( method 1) and LZ4 (method 2). The new method read from the binary header resolves to method 12... anyone have any idea what they are up to?