Copy and paste the following text:

-----------Start------------------
REGEDIT4

[HKEY_LOCAL_MACHINE\SOFTWARE\Westwood\Renegade\Ranks]
"M01"=dword:00000005
"M02"=dword:00000005
"M03"=dword:00000005
"M04"=dword:00000005
"M05"=dword:00000005
"M06"=dword:00000005
"M07"=dword:00000005
"M08"=dword:00000005
"M09"=dword:00000005
"M10"=dword:00000005
"M11"=dword:00000005
"M13"=dword:00000005
-----------Stop-------------------

Save it as ranks.reg and run it to have all 5 stars for every mission !