Blackbox Inno Setup Script

[M3HDI]

i configed the Archive.ini with this code :

if not ShowChangeDiskWindow ('Please Insert Disk To Continue...', ExpandConstant('{src}'),'Data1.cab') then break;
if not ISArcExtract ( 0, 25, ExpandConstant('{src}\Data1.cab'), ExpandConstant('{app}'), '', false, '', ExpandConstant('{tmp}\arc.ini'), ExpandConstant('{app}'), False) then break;
if not ShowChangeDiskWindow ('Please Insert Disk 2 To Continue...', ExpandConstant('{src}'),'Data2.cab') then break;
if not ISArcExtract ( 0, 25, ExpandConstant('{src}\Data2.cab'), ExpandConstant('{app}'), '', false, '', ExpandConstant('{tmp}\arc.ini'), ExpandConstant('{app}'), False) then break;
if not ShowChangeDiskWindow ('Please Insert Disk 3 To Continue...', ExpandConstant('{src}'),'Data3.cab') then break;
if not ISArcExtract ( 0, 25, ExpandConstant('{src}\Data3.cab'), ExpandConstant('{app}'), '', false, '', ExpandConstant('{tmp}\arc.ini'), ExpandConstant('{app}'), False) then break;
if not ShowChangeDiskWindow ('Please Insert Disk 4 To Continue...', ExpandConstant('{src}'),'Setup-2.bin') then break;
if not ISArcExtract ( 0, 25, ExpandConstant('{src}\Data4.cab'), ExpandConstant('{app}'), '', false, '', ExpandConstant('{tmp}\arc.ini'), ExpandConstant('{app}'), False) then break;

because i want use for 4 DVDs game
when runing the setup and Data1.cab has been extract
Setup display to me a window for next file
but this window NO Have OK Button and just have 2 button (Browse&Cancel)
how to add the button in the Setup?