Work-in-progress Lemmings 2 level editor by GuyPerfect

Editor:

    Left and Right keys load different stages.
    Up and Down keys specify the zoom factor.
    Hold Spacebar to display and move the default screen position.
    1 and 2 keys select if Objects or Presets are displayed in the picker.
    Backspace toggles Reveal mode.
    3, when Tile and Preset elements are selected, toggles background status. This can be determined with Reveal mode.
    Delete deletes the selected elements.
    Left-click and drag will either move an element or draw a selection box.
    Right-click and drag will pan the display.
    Shift forces an all-inclusive selection box. Ctrl forces an inversion selection box.
    Click and drag the dotted lines to resize the stage.
    Scroll Up and Scroll Down on the mouse specify the zoom factor.
    Chains, cannons, catapults and steam jets aren't implemented yet.
    The S key will save the current stage to a file called LEVEL___.DAT.
    Some objects in levels (namely many steel blocks on the Polar tribe) will not load.
    Clicking an element in the picker box will let you place one in the level.
    Click-and-drag when placing steel blocks, water or presets to insert multiples into the level.
    Esc will deselect selected objects and picked elements.

The resulting LEVEL___.DAT file is required for the skill selector to work. The skill selector can modify the following:

    Level name
    Time limit (minutes and seconds)
    Release rate (up to 20, and negative values possible. Needs investigation)
    All 8 skills and their quantities