Hi, I noticed a bug or misleading behavior with the <packdoubles> setting. The tutorial says the default behavior is "no" and doesn't need to be specified. Normally this means you can still specify it for clarity, but in this case, setting <packdoubles>no</packdoubles> WILL allow doubles. Not specfiying does not allow doubles, as expected.
Tested with this simple pack:
<pack>
<packtitle>20 Personae</packtitle>
<packimage>samplebooster</packimage>
<packkind>20 Random Personae</packkind>
<packdoubles>no</packdoubles>
<packcommoncrit><field>Set</field><eval>IS</eval><data>Main</data></packcommoncrit>
<chance>
<kind><qty>20</qty><crit><field>Set</field><eval>IS</eval><data>Main</data></crit></kind>
</chance>
</pack>
Cheers!