My extensions include:
- Added 1-bit transfer support for using sprites while loading.
- Added optional buffer-less block receive support (RECEIVE_BUFFER = 0 saves 254 bytes on the C=64, with some speed trade-off).
- Added support for ByteBoozer 2.0 (which does not require a depack buffer on the C=64), Pucrunch and Exomizer files.
For reference, this is the code I used to put together my disk version of Barbarian II.