This little bug is a pain, but luckily only shows up on certain configs…
So far, it seems to be an issue that only surfaces with Apache2.0 and PHP5, on Windows.. and is caused by the chdir(..) call - the main one being phpmyadmin.css.php. Change the “..” to your root directory, and all should be solved.
BTW [...]

if the installer just bails on the initial screen, make sure that the computer has a domain set up in the networking dialog. This is used to auto-configure the install of Apache, and looks like there is no detection other than failure during the installation process.