Vlad:
There is on your ship little red arrowheads. These are called "hard points". These are what you to what you fit your various components of your ship.
Now, down at the bottom of the left hand side of the screen, you may or may not see a button with the word, "Place" on it lit up. If it is lit up, you can place your item, but you may get a warning from the robot that the particular item you're trying to place is too big for the ship's size. You, ergo, have to find something a tad smaller.
Remember, a button with the word, "Place" and red arrowheads. You'll do fine if you remember those things.
Sincerely yours always,
Indy.
