Hmm.. the Jot wiki says this for the &placeholders parameter:
* 0 = no placeholders are created (default)
* 1 = placeholders are created for every debug value (see &debug parameter)
o if no tagid is specified the placeholders are created like this:
[+jot.html.form+]
o if the tagid is specified the placeholders are created like this:
[+jot.html.form.tagid+]
So, put the jot placeholders back in to the mgPictureTplComment chunk and use these:
[+jot.html.moderate.[+maxigallery.picture.id+]+]
[+jot.html.comments.[+maxigallery.picture.id+]+]
[+jot.html.form.[+maxigallery.picture.id+]+]
[+comment.custom.email.[+maxigallery.picture.id+]:is=``:then=``:else=`[+comment.custom.email.[+maxigallery.picture.id+]:gravatar+]`+]
I’m not sure if that custom field will work like that with the phx and all.. but if not, you could create a snippet to output all these placeholders and use it in the maxigallery template, eg.
[[MySnippet? &tagid=`[+maxigallery.picture.id+]`]]
<?php
return '[+jot.html.moderate.'.$tagid.'+]' .
'[+jot.html.comments.'.$tagid.'+]' .
'[+jot.html.form.[+maxigallery.picture.id+]+]' .
'[+comment.custom.email.'.$tagid.':is=``:then=``:else=`[+comment.custom.email.'.$tagid.':gravatar+]`+]';
?>
That should work atleast.