Here is a list of bitmaps available for item boxes:
MiniSamus        The small samus in a standing position 11x21
MorpSamus        Morph ball of Samus                    7x7
MinArrowU        Arrow pointing up                      7x8
MinArrowD        Arrow pointing down                    7x8
MinArrowL        Arrow pointing left                    8x7
MinArrowT        Arrow pointing right                   8x7

Also, the words seen in the game, like select and press, are bitmaps.
The following words are available for use in the Draw funtion:
PButton, PIt, PThe, PWith, PSet, PAnd, PPress, PSelect
Note:  PAnd is actually a &

Here is a list of functions for the drawing:

Text("Text", xposition, yposition, r, g, b)
Text used for descriptions.  Never used in original SM, SMTC only!

Draw("Bitmap", xposition, yposition)
Draws the bitmap at the given position.  The bitmap can be any of the presets
listed above, or it can be any custom made sprite, or any universal sprite
object.

Control("Name", xposition, yposition)
When instructing the user on what button to press, use this.  In the original
Super Metroid, this was limited to X, Y, A, and B.  In SMTC, this can be any
key on the keyboard and some joypad keys.  The following names can be applied

MakeSmall()
Makes the item box smaller (150x24).  The box is large by default.
Coordinates are still relative to the top left of a large box, though.
The new top left of the box will be located at (24, 8).

AngD, AngU, Jump, Shoot, Run, ISwitch, Left, Right, Up, Down
Debug1, Debug2, Debug3, AntiGrav, ReGrav, PixRight, PixLeft
These are the same as the config names.

All x and y coordinates are relative to the top of the box shown for items.
Any x value exceeding 208 or y value exceeding 48 will be invisible.

To create a function for an item, enter its name and then all the drawing
functions.
When you are done, enter ENDname.
Example:

BOMB
Draw(MiniSamus, 32, 5)
ENDBOMB

A list of all names supported as of this release:

SPAZERBEAM
PLASMABEAM
CHARGEBEAM
ICEBEAM
BURNBEAM
WAVEBEAM
BURNBEAM
VARIASUIT
GRAVITYSUIT
CORROSIONSUIT
MORPHBALL
BOMB
SPRINGBALL
SPEEDBOOSTER
HIGHJUMPBOOTS
SPACEJUMP
SCREWATTACK
MISSILE
SUPERMISSILE
POWERBOMB
ENERGYTANK
RESERVETANK
GRAPPLINGBEAM
XAYSCOPE
SAVECOMPLETE
SHIPRESTORE
ENERGYRESTORE
MAPPINGCOMPLETE
MISSILERESTORE

Because there is no Corrosion Suit item as of yet, you will not be required
to make one just yet.