button ID, Text [,"Icon"] [,"Script"]

Creates or alters a button which is placed in a message box. The command must be executed AFTER the command msgbox, because msgbox deletes all buttons again.
ID is the ID for access to the button. It must be between 0 and 9. The parameter Text defines the caption.
The parameter Icon determines which icon is used for the button (sys\gfx\icons.bmp). Each icon has an ID, beginning with 0 at the upper left corner and then increasing to the right and downwards as you read. Alternatively, you can insert the path to an image file (in relation to the mod folder). The picture should be 32 square pixels in size and use 255,0,255 as masking colour.
For Script, fill in the ID of an info to use its text or enter a file name to load the text from it. If there is no parameter Source attached, the text from the buffer will be used and the buffer will be emptied right next. The button script will only be executed on clicking the button and therefore does not require events (whoever may feel like it can nevertheless use the event on:click).
Alternatively, an event can be inserted for Script (may not contain a full stop or a semicolon). This event will be executed on global level each time you hit the button.