Hello,

It seems that there is way to enable subtitles in Windows version but I have a OS X.
How I can get the english subtitles in this mac-version?

Subtitles are only present in the floppy version, so you need to find and run Simon the Sorcerer (Floppy).

Yeah, I know. And thats the situation with the Windows version. After installation there should be two different executables under Start Menu. Simon The Sorcerer and Simon The Sorcerer (floppy).

But in mac-version the floppy-version seems to be missing. There's only one Simon the Sorcerer.app inside the .dmg file. Should there be two different applications, I don't know. Only GoG team knows that...

Did you send a support ticket?
http://www.gog.com/support/contact

It is missing (for quite some time now), so no need to search for it. Until GOG staff adds the floppy version for Mac, your only option is to get the Windows version running.
You could install the game via Darwine.
Then start scummvm.exe through Darwine
Choose "Add Game..."
Select the folder "DOS" and press "Choose".
You can now configure some options for the game and play it.

You might run into troubles using ScummVM within Darwine though. Alternative download and install the Mac version of ScummVM (http://scummvm.org/downloads/). You still need to extract the content from GOG's Windows version, by installing it through Darwine. Inside the installation is a folder called "DOS", that's the floppy version. Copy this folder to your preferred location, start ScummVM (Mac) and add the game.