OK, I have managed to get the page to load now, by changing;
<option value="<?php echo $row_WADADynListhandler['id']?>" <?php if (!(strcmp("<?php echo $row_WADADynListhandler['id']?>", (isset($_GET["invalid"])?ValidatedField("qualifiedteaminsert","handler_name"):"")))) {echo "selected=\"selected\"";} ?>><?php echo $row_WADADynListhandler['handler_f_name']?></option>
to
<option value="<?php echo $row_WADADynListhandler['id']?>" <?php if (!(strcmp($row_WADADynListhandler['id'], (isset($_GET["invalid"])?ValidatedField("qualifiedteaminsert","handler_name"):"")))) {echo "selected=\"selected\"";} ?>><?php echo $row_WADADynListhandler['handler_f_name']?></option>
I haven't tested the page yet, but was wondering why WA CSS Form Builder was creating the original code....?