Requirements and first installation:
1) A webserver.
An easy solution is to use Xampp or Lampp

a)Windows : Just download and install xampp (the installer).
When the installation is done, you will find XAMPP under Start - Programs - XAMPP.
You can use the XAMPP Control Panel(xampp-control.exe) to start/stop all server and also install/uninstall services.

b) Linux : Download the tar.gz file.
Now run the command from the console :
sudo tar xvfz xampp-linux-1.7.tar.gz -C /opt
Start lampp with : sudo /opt/lampp/lampp start
Stop lampp with : sudo /opt/lampp/lampp stop
Now start apache and MySQL and test them by opening the browser at the address :
http://localhost/xampp
Hit the phpinfo() link in order to get important informations like the PHP version or just go with your browser at the address :
http://localhost/xampp/phpinfo.php

2) You have to enable bcompiler on your webserver.
By default is not enabled.

a)Windows :

i)Install Xdebug
-Download Xdebug dll (notice that you have to know your PHP version from phpinfo)
-Open xampp\php\php.ini and make these changes :

[Zend]
;zend_extension_ts = "E:\YOUR_PATH\xampp\php\zendOptimizer\lib\ZendExtensionManager.dll"
;zend_extension_manager.optimizer_ts = "E:\YOUR_PATH\xampp\php\zendOptimizer\lib\Optimizer"
;zend_optimizer.enable_loader = 0
;zend_optimizer.optimization_level=15
;;zend_optimizer.license_path =
;; Local Variables:
;; tab-width: 4
;; End:

[XDebug]
;; Only Zend OR (!) XDebug
zend_extension_ts="E:\YOUR_PATH\xampp\php\ext\php_xdebug.dll"
xdebug.remote_enable=true
xdebug.remote_host=127.0.0.1
xdebug.remote_port=9000
xdebug.remote_handler=dbgp
xdebug.profiler_enable=1
xdebug.profiler_output_dir="E:\YOUR_PATH\xampp\tmp"

-Do the same thing at the file xampp\apache\bin\php.ini
By doing this we disable the Zend optimizer and we are using Xdebug instead.
-Put the php_xdebug.dll at the
E:\YOUR_PATH\xampp\php\ext\php_xdebug.dll
If you have problems with apache (errors like dll not found) then you should download another version of xdebug.dll (always rename it to php_xdebug.dll) from xdebug.org
-Now stop and restart xampp (apache+MySQL).
Under http://localhost/xampp/phpinfo.php you should now find the xdebug.

ii)Install bcompiler
-Go to xampp\php\php.ini and uncomment :
extension=php_bcompiler.dll
-Do the same for the file xampp\apache\bin\php.ini
extension=php_bcompiler.dll
-Now stop and restart xampp (apache+MySQL).
Under http://localhost/xampp/phpinfo.php you should now find the bcompiler too.
-Now you are ready to use Bcompiler GUI under Windows!
b)Linux (Tested on Kubuntu) :
-Download and install these packets :
sudo apt-get install php5-dev
sudo apt-get install automake m4
sudo apt-get install libbz2-dev
sudo apt-get install re2c
sudo apt-get install php-pear

-Then do :
sudo pecl install bcompiler-0.8
bcompiler with this command should be compiled and inserted at this folder :
/usr/lib/php5/20060613+lfs
-Open the file
/etc/php5/cli/php.ini
and write
extension=bcompiler.so
in order to activate bcompiler
-Copy the
/usr/lib/php5/20060613+lfs/bcompiler.so
into the folder
/opt/lampp/lib/php/extensions/no-debug-non-zts-20060613/bcompiler.so
-Open the file
/opt/lampp/etc/php.ini
and write
extension="bcompiler.so"
in order to activate bcompiler
-Now stop the server
sudo /opt/lampp/lampp stop
-Now start the server
sudo /opt/lampp/lampp start
-Under http://localhost/xampp/phpinfo.php
you should now find the bcompiler.

3) Firefox 3.
Is needed for launching the script CompileScript.php under Linux.
Under Windows Firefox is not needed but it is always recommended to have it.

How to use :
1) Start apache and MySQL
2) Select your webserver root . Must be something like
/opt/lampp/htdocs/ (under Linux)
c:\xampp\htdocs\ (under Windows)
3) Select your PHP project to compile (website root).
This must be under the webserver root for example :
/opt/lampp/htdocs/mysite (under Linux)
c:\xampp\htdocs\mysite (under Windows)
4) Select your PHP files that you want to compile.
By default they are all selected.
Note that the Compiled project will be generated at :
/opt/lampp/htdocs/mysiteCompiled (under Linux)
c:\xampp\htdocs\mysiteCompiled (under Windows)
Notice that under Linux you have to CHMOD 777 the /opt/lampp/htdocs/mysiteCompiled directory and all the underneath subirectories too.
5) Press the Compile button.
6) You are almost done.
If you get a series of warnings like :
Warning: fopen(index.php).
Just make sure that /opt/lampp/htdocs/mysiteCompiled is CHMOD 777 and then just reload the webpage with firefox.
The url should be something like that :
http://localhost/mysiteCompiled/CompileScript.php
7) If you got a successfull compilation it is time to test your compiled site by going at :
http://localhost/mysiteCompiled/
(or just hit the link at the 'all done' page.)
8) If it everything alright then you must delete the CompileScript.php script.
9) All done !

Important Notes :
The compiled version of your PHP product needs a webserver with bcompiler enabled.

Bcompiler GUI can work with Wampserver too.
Download and install Wampserver (any edition).
Download and install Wampserver PHP Addons Version php 5.2.5
Click on Wampserver -> PHP -> Version -> 5.2.5 from Taskbar (it will change your current version of php to 5.2.5).
Select Wampserver -> PHP -> extension -> php_bcompiler (it will enable bcompiler on your computer). Now you can use Bcompiler GUI.
Select the Folder on the Bcompiler GUI and this will compiler your whole website with one click.