Oh boy, the game screen has more buttons than an Airbus Cockpit. Gabriel Knight is a fantastic game, but the interface surely can get confusing for even veteran adventure game players. According to Jane Jensen in the making of Gabriel Knight video, the high number of icons is to get more gameplay depth. It is the only Sierra game to our knowledge that has 8 different action icons though, so we assume Sierra stepped away from this interface after Gabriel Knight 1. Ok, let's go through them.
The WALK icon obviously allows the player to move Gabriel around.
The LOOK icon allows to observe and get description of people, items and so, often revealing clues.
The ASK icon allows Gabriel to interrogate people if applicable. When using this icon, the game will go into the interrogation screen, allowing the player to select various subjects. As the game proceeds and more clues are revealed, you may have to speak to the same people multiple times as the list of topics updates.
The TALK icon is not the same as the ASK icon. It provides general chitchat and sometimes clues. The player does not go into interrogation mode with this icon.
The PICK UP icon really means just that: to pick up things. It cannot be used to move things, to open doors, to push a button and so on. Most things that are picked up, get stored in Gabriel's inventory, others (such as the daily newspaper) is placed back on its location in the game.
The OPEN icon is not only used to open doors, but also drawers, envelopes, anything that can be opened.
The OPERATE icon is used to operate mechanisms, such as the clock in grandma's attic, the temperature control outside Mosely's office and so on. It can get confusing though, as it is for example also used for Gabriel to wash his hands in the snow. Took a whie to figure out which icon to use there.
The MOVE icon is rarely used in the game but nonetheless essential. Used it to move things around, for example to insert the metal bars into the holes of the tomb stone, or to move the clock on grandma's attic.
Click on the INVENTORY icon in the main game screen to access the inventory window. And what have we here? More buttons!
These icons can also be confusing. For example if the player wants to read a book, does he need to use the READ icon, the OPEN (the book) icon, or the LOOK icon?
Notice also the slider-bar. Near the end of the game the player will have some 4 screens stuffed with inventory items, so the slider-bar allows to toggle through them.
Also keep in mind that inventory items can be combined in the inventory screen. For example you will want to have a close look at the various snake scales with the magnifying glass.
To select an inventory item to use in the main game screen, use the arrow icon on it and click the PLAY button. The selected inventory item will appear in the small window at the top of the screen. Sometimes you will want to prepare an inventory item in advance to have quick access. One example would be to prepare the clay before talking to Madame Cazaunoux.
Tape recorder screen
Designed for those who would like to hear certain conversations again to refresh the memory or for Gabriel to violate human rights. In truth, you don't really need it (unlike in Gabriel Knight 2 where it is actively used to progress in the game).
Click the tape recorder icon in the main game screen to access it. After selecting a tape, the player will see a list of discussed topics, as in the interrogation screen (only the interrogations are recorded). Click on one of the topics and another window shows up where the player can skim through each individual sentence of the conversation.
Click the control panel button on the main game screen to access the control panel window. In this window the player can save, restore, restart or quit the game. There are also various settings, such as the game speed and volume controls.
The narrator voice can be disabled (though it is recommended to at least enable the subtitles then as her comments often contain clues). The HIDE icon is to hide the toolbar on the main game screen, so it only appears when the mouse pointer is moved over it. The ABOUT icon shows copyright information, game credits, how-to-play and some hints.