Q: Problems to connect the MacBook Pro to the home theater.

First, what model macbook pro do you have? If it is mid 2010 or later, you should be able to get audio out via an hdmi adapter, according to this information.  Otherwise, you'll only get the video signal, and will need to connect up audio some other way.

Another question - does your TV to amplifier connection support audio return?

Do you also have an hdmi cable running from your tv to your amplifier, and if so, does it support audio return? If so, you would just need to choose the appropriate input in your amplifier - might even do this automatically. (This is how I have my system set up.) If you don't have an audio return channel, then you could run an optical cable from your powerbook's audio jack to an optical input in your amplifier, using a cable such as this one.

My pleasure. In case you are sending multichannel audio, you may need to tweak the settings in Audio MIDI Setup (in Applications > Utilities) after you have it cabled up.