我看了一下，具体的解压的话，请参考ULZMAAlone.pas中的下面这一段：

if inStream.read(properties, propertiesSize) <> propertiesSize then
raise Exception.Create(‘input .lzma file is too short’);
decoder := TLZMADecoder.Create;
if not decoder.SetDecoderProperties(properties) then
raise Exception.Create(‘Incorrect stream properties’);
outSize := 0;
for i := 0 to 7 do begin
v := {shortint}(ReadByte(inStream));
if v < 0 then raise Exception.Create('Can''t read stream size'); outSize := outSize or v shl (8 * i); end; if not decoder.Code(inStream, outStream, outSize) then raise Exception.Create('Error in data stream'); decoder.Free;