If you give me a xml format to follow, i could add it down the line. But I know nothing of ISBoxer so i would need some directions on what you want me to generate (and it would come after some other of my todos :-)
I'm not picky As long as it's valid XML, and has a list of each of the macros that'd be cool, with an attribute or a separate name or something marking the master macro.

Something like this would be perfect, example XML below created from this guy's macros: http://www.dual-boxing.com/showthread.php?t=23481
Code:
<?xml version="1.0" encoding="UTF-8"?>
<Macros>
    <Macro name="Master">/Click MultiBarRightButton5
/Click MultiBarRightButton6
/Click MultiBarRightButton7
/Click MultiBarRightButton8
/Click MultiBarRightButton9
/use 13
/use 14
/Petattack
/cast Demonic Empowerment
</Macro>
    <Macro name="MultiBarRightButton5">#show Life Tap
/cast [mod, nochanneling] Drain Soul
/castsequence [nochanneling] reset=combat Life  Tap,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,  ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
</Macro>
    <Macro name="MultiBarRightButton6">#show Curse of Agony
/cast [mod, nochanneling] Drain Soul
/castsequence [nochanneling] reset=target Curse of  Agony,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,, ,,,
</Macro>
    <Macro name="MultiBarRightButton7">#show Corruption
/cast [mod, nochanneling] Drain Soul
/castsequence [nochanneling] reset=target  Corruption,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
</Macro>
    <Macro name="MultiBarRightButton8">#show Immolate
/cast [mod, nochanneling] Drain Soul
/castsequence [nochanneling] reset=target  Immolate,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
</Macro>
    <Macro name="MultiBarRightButton9">#show Shadow Bolt
/cast [mod, nochanneling] Drain Soul
/cast [nochanneling] Shadow Bolt
</Macro>
</Macros>