set command broken by "//"

Regarding your last question about the replacement of "//", as an example here's how I'd go after manipulating the query to remove the "//" from "http://".

 when HTTP_REQUEST { 
  
 set orig_query [HTTP::query] 
 set new_query [string map {"http://" "http:"} $orig_query] 
 log local0. "New query is $new_query" 
  
 } 

Note: I've overly used variables for the sake of the example. You could very well simplify (and save cycles) to a single line like:

set new_query [string map {"http://" "http:"} [HTTP::query]]

HTH,

-Matt