Frends Process editor have some keyboard shortcuts:

Arrows: move view

C : Activates Connect tool
E : Add name to element
H : Activates Hand tool
L : Activates Lasso tool
S : Activates Create/remove space tool

Ctrl+C : Copy selected element(s).
Ctrl+V : Paste selected element(s).
Delete: Delete selected element(s).

Holding Ctrl  down while selecting elements lets you click and select multiple elements.
Holding Sift  down while dragging over canvas lets you select elements within area.

Ctrl+F: Search element in process.
Ctrl+F (inside parameter editor): Opens a search/replace tool.