For future reference for newbies like myself ...

When migrating my site to a new server - I was just getting a blank screen - with no error logs being generated at all (even after adding show errors in the system/localconfig.php file).

When running the install.php - I would get prompted for the install password OK, but after that just a blank screen.

The reason is that CentOS "yum install php" only installs PHP. Other php plugins are required. I added the ones that were installed on my old server and all is then OK. I think that the important ones are:
- php-mysql (of course!)
- php-soap

And others - In the /etc/php.d directory I have:
-rw-r--r-- 1 root root 51 Jan 21 2009 dbase.ini
-rw-r--r-- 1 root root 47 Jan 21 2009 dom.ini
-rw-r--r-- 1 root root 45 Jan 21 2009 gd.ini
-rw-r--r-- 1 root root 49 Jan 21 2009 imap.ini
-rw-r--r-- 1 root root 49 Jan 21 2009 ldap.ini
-rw-r--r-- 1 root root 53 Jan 21 2009 mysqli.ini
-rw-r--r-- 1 root root 51 Jan 21 2009 mysql.ini
-rw-r--r-- 1 root root 47 Jan 21 2009 pdo.ini
-rw-r--r-- 1 root root 59 Jan 21 2009 pdo_mysql.ini
-rw-r--r-- 1 root root 59 Jan 21 2009 pdo_pgsql.ini
-rw-r--r-- 1 root root 61 Jan 21 2009 pdo_sqlite.ini
-rw-r--r-- 1 root root 51 Jan 21 2009 pgsql.ini
-rw-r--r-- 1 root root 59 Jan 21 2009 xmlreader.ini
-rw-r--r-- 1 root root 53 Jan 21 2009 xmlrpc.ini
-rw-r--r-- 1 root root 59 Jan 21 2009 xmlwriter.ini
-rw-r--r-- 1 root root 47 Jan 21 2009 xsl.ini

I used this list to decide what to install with yum.

Suggestions:
- The INSTALL.txt file only mentions GDLib and mcrypt. It would be good of all the extentions are detailed.
- Also I am not sure if it would be possible to log an error in the case that mysql extention is not available at all?

I hope you don't mind my feedback?

Also, for the avoidance of doubt
- the database backup and restore using Webmin was OK (no problem with blobs).
- php 5.1.6 is OK

Adrian