Some questions about Zstd

Some questions about Zstd

Huffman Literals: what is the minimum header bytes?
Huffman Fse:
what is the minimum weights number should we put (include missing weight)?
in spec
4.Stream4_Size = Total_Streams_Size - 6 - Stream1_Size - Stream2_Size - Stream3_Size.
Note: if Stream1_Size + Stream2_Size + Stream3_Size > Total_Streams_Size, data is considered corrupted.
is the correct note is:
total_stream_size < stream1+stream2+stream3 sizes +6+1? ( 1 because minimum stream 4 byte is 1)?
Lit stream: is regenerated size should be zero? is compressed size should be zero?
Fse sequence - should we configured by mistake offset size 0 ?
Block size: is 128k limitation for compressed sizes: it include block header (3 bytes) or not?
Thanks,
Shuli,