Attached are 64-bit 7-Zip binaries which use the new library. I'll put the source on github soon. They are v 17.01 because I haven't merged v 18 yet.
In the GUI, the initial word size setting may be loaded from the registry. It's best to initialize by changing the level because the default values are higher than normal 7z.
The compression levels use the same dictionary size as normal 7z, which results in a little less compression because the MF is a block algorithm. Bumping the level up one tends to even it out. Size at level 8 & 9 is higher than normal 7z at 128Mb.
Note the low multithread memory usage
EDIT: attached an updated version due to a bug in my 7-zip stream handler which caused it to infinite loop after the library finished compressing, if dict > input size. This version has smoother progress updates too.
EDIT 2: Fixed a crash when progress is set to NULL, e.g. with filters like BCJ2
EDIT 3: It has now passed plenty of automated testing and is released on github for x86 and x64: https://github.com/conor42/7-Zip-FL2/releases/