there are 3 steps to fixing these "missing xxx" or xxx required problems in Laravel/PHP
1) install the system libraries. Curl, mcrypt, zip all have corresponding .so libraries and .h header files which you have to install first.
>sudo yum install libmcrypt-devel
2) install the php extension which acts as a wrapper for these c++/c system libs.
>sudo yum install php-mcrypt..
3) recompile php with the mcrypt option so it knows to load the header files...
>./configure --with-curl --with-mcrypt --enable-zip
make sure to keep the other options as you keep on debugging.