Below is the list of TheIDE special features:
Use Ctrl+Tab to cycle through files. This is perhaps the most used key in TheIDE!
Use Alt+Left to "return" to important places (e.g. where you have written something). Use Alt+Right to cycle this places forward.
Esc key closes (and reopens) the bottom pane (with compilation results etc...)
Rectangular blocks are activated by pressing ALT key.
You can copy files (Ctrl+C in system file manager, Ctrl+V in TheIDE) into text directly. If more than single file is on clipboard, all text is copied.
Dragging file onto TheIDE opens it (as "temp" file).
Use Ctrl+/ to hide project overview - useful e.g. when editing wide layouts.
Use Ctrl+-, Ctrl+| to split editor vertically/horizontally.