[Zope] sql INSERT during query

[Jay, Dylan]

I am trying to add a new record to a table based on the query to another
table. Everytime I try this I get a "400 Bad Request" error with no debug
info. Is there any reason why I can't do what I require?

I am using a URL like
"Download/qryGetUnregUser/MagicNumber/14777794/completeReg"
where qryGetUnregUser is

select *
from unregUsers
WHERE MagicNumber = <!--#sqlvar MagicNumber type=string-->

and completeReg is

<!--#var standard_html_header-->
<h2><!--#var title_or_id--></h2>
   <!--#var qryAddRegUser-->
   <p> Thank you <!--#var fullName--> for taking the time
       to register. You have been succesfully registered.
       You may now enter restricted parts of this site by
       entering your username <i><!--#var username--></i>
       and password.</p>
<!--#var standard_html_footer-->

and qryAddRegUser is

INSERT INTO users VALUES (
<!--#sqlvar HRID type="string"-->,
<!--#sqlvar username type="string"-->,
<!--#sqlvar email type="string"-->,
<!--#sqlvar fullName type="string"-->,
<!--#sqlvar password type="string"-->,
<!--#sqlvar position type="string"-->,
<!--#sqlvar orgCode type="string"-->,
'Customer',
''
)

I have tried making completeReg have proxy Manager permission. 
What am I doing wrong?