Hereby a guide.
First add these lines to mylinks/xoops_version.php
 $modversion['blocks'][3]['file'] = "mylinks_top.php"; 
$modversion['blocks'][3]['name'] = _MI_MYLINKS_BNAME3; 
$modversion['blocks'][3]['description'] = "Shows random web links"; 
$modversion['blocks'][3]['show_func'] = "b_mylinks_random"; 
$modversion['blocks'][3]['edit_func'] = "b_mylinks_random_edit"; 
$modversion['blocks'][3]['options'] = "random|1|19"; 
$modversion['blocks'][3]['template'] = 'mylinks_block_random.html';  
after
 $modversion['blocks'][2]['file'] = "mylinks_top.php"; 
$modversion['blocks'][2]['name'] = _MI_MYLINKS_BNAME2; 
$modversion['blocks'][2]['description'] = "Shows most visited web links"; 
$modversion['blocks'][2]['show_func'] = "b_mylinks_top_show"; 
$modversion['blocks'][2]['edit_func'] = "b_mylinks_top_edit"; 
$modversion['blocks'][2]['options'] = "hits|10|25"; 
$modversion['blocks'][2]['template'] = 'mylinks_block_top.html';  
Add the following to mylinks/languages/english/modinfo.php
 define("_MI_MYLINKS_BNAME3","Random Link");  
Replace the file mylinks/blocks/mylinks_top.php with this one:
 // $Id: mylinks_top.php,v 1.11 2004/12/26 19:11:56 Onokazu Exp $ 
//  ------------------------------------------------------------------------ // 
//                XOOPS - PHP Content Management System                      // 
//                    Copyright (c) 2000 XOOPS.org                           // 
//                                                    // 
//  ------------------------------------------------------------------------ // 
//  This program is free software; you can redistribute it and/or modify     // 
//  it under the terms of the GNU General Public License as published by     // 
//  the Free Software Foundation; either version 2 of the License, or        // 
//  (at your option) any later version.                                      // 
//                                                                           // 
//  You may not change or alter any portion of this comment or credits       // 
//  of supporting developers from this source code or any supporting         // 
//  source code which is considered copyrighted (c) material of the          // 
//  original comment or credit authors.                                      // 
//                                                                           // 
//  This program is distributed in the hope that it will be useful,          // 
//  but WITHOUT ANY WARRANTY; without even the implied warranty of           // 
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the            // 
//  GNU General Public License for more details.                             // 
//                                                                           // 
//  You should have received a copy of the GNU General Public License        // 
//  along with this program; if not, write to the Free Software              // 
//  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA // 
//  ------------------------------------------------------------------------ // 
/****************************************************************************** 
 * Function: b_mylinks_top_show 
 * Input   : $options[0] = date for the most recent links 
 *                    hits for the most popular links 
 *           $block['content'] = The optional above content 
 *           $options[1]   = How many reviews are displayes 
 * Output  : Returns the desired most recent or most popular links 
 ******************************************************************************/ 
function b_mylinks_top_show($options) { 
    global $xoopsDB; 
    $block = array(); 
    $myts =& MyTextSanitizer::getInstance(); 
    $result = $xoopsDB->query("SELECT lid, cid, title, date, hits FROM ".$xoopsDB->prefix('mylinks_links')." WHERE status>0 ORDER BY ".$options[0]." DESC",$options[1],0); 
    while($myrow = $xoopsDB->fetchArray($result)){ 
        $link = array(); 
        $title = $myts->makeTboxData4Show($myrow["title"]); 
        if ( !XOOPS_USE_MULTIBYTES ) { 
            if (strlen($myrow['title']) >= $options[2]) { 
                $title = $myts->makeTboxData4Show(substr($myrow['title'],0,($options[2] -1)))."..."; 
            } 
        } 
        $link['id'] = $myrow['lid']; 
        $link['cid'] = $myrow['cid']; 
        $link['title'] = $title; 
        if($options[0] == "date"){ 
            $link['date'] = formatTimestamp($myrow['date'],'s'); 
        }elseif($options[0] == "hits"){ 
            $link['hits'] = $myrow['hits']; 
        } 
        $block['links'][] = $link; 
    } 
    return $block; 
} 
 
function b_mylinks_random( $options ) 
{ 
global $xoopsDB, $xoopsModuleConfig; 
    $block = array(); 
    $myts =& MyTextSanitizer::getInstance(); 
    $result = $xoopsDB->query("SELECT lid, cid, title, url, date, logourl FROM ".$xoopsDB->prefix('mylinks_links')." WHERE status>0 ORDER BY RAND() LIMIT 1 "); 
    while($myrow = $xoopsDB->fetchArray($result)){ 
 
        $title = $myts->makeTboxData4Show($myrow["title"]); 
        if ( !XOOPS_USE_MULTIBYTES ) 
                 { 
                    if ( strlen( $title ) >= $options[2] ) 
                    { 
                      $title = substr( $title, 0, ( $options[2] -1 ) ) . "..."; 
                    }  
                 } 
        $block['id'] = $myrow['lid']; 
        $block['cid'] = $myrow['cid']; 
        $block['title'] = $title; 
        $block['url'] = $url; 
        $block['logourl'] = $myrow['logourl']; 
        $block['date'] = formatTimestamp($myrow['date'],'s'); 
        //$block['random'][] = $random; 
    } 
    return $block; 
} 
 
function b_mylinks_top_edit($options) { 
    $form = ""._MB_MYLINKS_DISP." "; 
    $form .= "; 
    if($options[0] == "date"){ 
        $form .= "date'"; 
    }else { 
        $form .= "hits'"; 
    } 
    $form .= " />"; 
    $form .= ".$options[1]."' /> "._MB_MYLINKS_LINKS.""; 
    $form .= " 
"._MB_MYLINKS_CHARS." .$options[2]."' /> "._MB_MYLINKS_LENGTH.""; 
 
    return $form; 
} 
 
function b_mylinks_random_edit( $options ) 
{ 
    $form = "" . _MB_MYLINKS_CHARS . " "; 
    $form .= ". $options[2] . "' /> " . _MB_MYLINKS_LENGTH . ""; 
    return $form; 
} 
?>  
Create a file called mylinks_block_random.html in the folder mylinks/templates/blocks. This is the code for this file:
 <div align="center"> 
 
<a href="<{$xoops_url}>/modules/mylinks/visit.php?cid=<{$block.cid}>&lid=<{$block.id}>"><{$block.title}>a> 
 
<br /> 
 
<{$block.date}> 
 
<br /> 
             
<a href="<{$xoops_url}>/modules/mylinks/visit.php?cid=<{$block.cid}>&lid=<{$block.id}>" target="_blank"> <img src="<{$xoops_url}>/modules/mylinks/images/shots/<{$block.logourl}>" width="88" height="31" alt=""/>a>  
       
div>  
Good luck!!!