Can't really tell you anything else than what's in the instructions, but there are essentially three things to be done now to install it. You need the define the Trustpath and upload the corresponding files there, you need to upload some files to the regular modules directory (where all the modules reside), and you need to patch the mainfile.php. So let's start with the uploads:
1. Trust path: If you have the regular linux server, your website is most likely hosted in a directory called public_html or htdocs. Those are per system settings accessible by the wide world. So the idea with the trust path is to put most of the files that are important for the operation of your site, but which the world doesn't have to see ("see" means that there's a potential for tampering), in a location where the server can work with them, but the world cannot find them. Hence the trust path, which is a modification of the normal XOOPS infrastructure the author of the XOOPS protector module has introduced. It is quite astute. So the idea is that you create a directory which is NOT INSIDE your public_html or htdocs, but parallel to it. Create that directory and call it at your liking. Inside the directory, create another directory called "modules". Upload the entire directory called "protector" from xoops_trust_path/modules from the zip archive into it.
2. Upload the entire directory called "protector" from html/modules from the zip into the "modules" directory where you have all your regular XOOPS modules. It's probably a good idea at this juncture to go to your modules administration inside XOOPS and install the Protector module as you would install any other module. If it throws a lot of errors, try this again after the next step.
3. Now the patching of main.php: Ideally, it is write protected, so you have to change permissions to be able to edit/overwrite it. Locate the line in main.php that starts with: define('XOOPS_ROOT_PATH',... and insert another line next to it that reads:
define('XOOPS_TRUST_PATH','/path/to/your/trust-path');
Of course, you have to edit /path/to/your/... to your needs. It will start the same as the path declared as XOOPS_ROOT_PATH, but where XOOPS_ROOT_PATH will most likely end in htdocs or public_html, XOOPS_TRUST_PATH ends in whatever name you have given to that directory in the first step.
That was the first thing to take care of in mainfile.php. Now the pre-/post-check: Towards the end of mainfile.php, there should be a couple of lines that look something like this here (depending on the XOOPS version, it may vary a little):
if (!isset($xoopsOption['nocommon']) && XOOPS_ROOT_PATH != '' ) {
include XOOPS_ROOT_PATH."/include/common.php";
}
You have to add a line before and one after this, so that, in the end, it looks like:
include XOOPS_TRUST_PATH.'/modules/protector/include/precheck.inc.php' ;
if (!isset($xoopsOption['nocommon']) && XOOPS_ROOT_PATH != '' ) {
include XOOPS_ROOT_PATH."/include/common.php";
}
include XOOPS_TRUST_PATH.'/modules/protector/include/postcheck.inc.php' ;
Then save mainfile.php in its original location, and write protect it.
That should be all. The author's instructions are the ones that count. Just recapping it because I see that the instructions can be a little confusing. Hope this helps.