I just upgraded to 1.4.2 (thanks, Gideon - worked out a few plugin issues nicely); but I ran into the same problem I had initially installing q2a with a Wordpress Network:
Database query error 1146
Table 'wordpress.wp_8_users' doesn't exist
SELECT user_nicename, ID FROM wp_8_users WHERE ID IN (615,718,674,525,757,569)
The problem is it is using the $table_prefix variable, which points to the current blog (hence the 8_ after the prefix). That table doesn't exist in a network install. It would work if instead of calling
global $table_prefix;
we call:
global $wpdb;
and then insert:
$wpdb->base_prefix
in the two places with $table_prefix; this ensures that the table prefix is the base table prefix, not the current blog prefix.