QM internet functions currently don't allow to specify additional headers to send. It will be added in next QM version.
Now you can use this function:
Member function Http.Get3
function#$remotefile str&data [flags] [inetflags] [str&responseheaders] [$headers] ;;flags: 1-3 cache flags, 16 download to file, 32 run in other thread
;Downloads web page or other file. ;Returns: 1 success, 0 failed.
;remotefile - file to download, relative to server. Examples: "index.htm", "images/earth.jpg". ;data - variable that receives file data. If flag 16 - variable that contains local file name. ;flags, inetflags, responseheaders, headers - see <help>IntGetFile</help>. Does not support flags: 4, 8. For https use INTERNET_FLAG_SECURE in inetflags.
;REMARKS ;At first call Connect to connect to web server.