The command above works well if you are only spelling out one word. If you need to be able to spell out a phrase -- with a space maintained between words, try:
<?xml version="1.0" encoding="utf-16"?>
<!--VoxCommando 2.0.0.0-->
<command id="342" name="Spell more than one word {1}" enabled="true" alwaysOn="False" confirm="False" requiredConfidence="0" loop="False" loopDelay="0" loopMax="0" description="Use if you want to spell out more than one word at a time (i.e., a phrase), using the spelling dictation term "space" to separate the words.">
<action>
<cmdType>Results.SetLastResult</cmdType>
<params>
<param>{1}</param>
</params>
<cmdRepeat>1</cmdRepeat>
</action>
<action>
<cmdType>Results.RegExReplace</cmdType>
<params>
<param>(\b\s|\s\b)</param>
</params>
<cmdRepeat>1</cmdRepeat>
</action>
<action>
<cmdType>SendKeys</cmdType>
<params>
<param>{LastResult}</param>
</params>
<cmdRepeat>1</cmdRepeat>
</action>
<phrase>Spell</phrase>
<payloadDictation>payloadDictation: Spelling</payloadDictation>
</command>