Legend: have not figured out how to create this in OOM; did it in OCAD and then brought it over.
Key points for making maps in OOM
F6 Pan map
F7/F8 zoom in and out
Use map parts to isolate sets of items
E edit objects.
Nodes: square=normal. diamond=dash point. circle=curve handle. Add with Ctrl-click on empty spot (can move mouse same action). Dash point: space bar + Ctrl-click. Remove: Ctrl-click an existing note.
Moving: use dashed box. Ctrl: constrains movement angle. Shift: curor snaps to other existing objects
L edit lines
Click and drag. Toggl angle constraint by holding Ctrl.
Switch a line segment between curved and straight: hold Ctrl while clicking the segment.
S set point objects. Rotate point symbol by clicking and moving the mouse, or rotate pattern tool.
P draw paths
Lines (very different than OCAD): click on position of each corner. Last corner: right click or double click.
Smooth path: click and drag the mouse away in the continuing direction.
Mix straight and curved: click vs click-and-drag.
Snap to existing objects: hold Shift. To follow shape of existing object, click while holding Shift; drag the mouse along it.
Constrain drawing angle by holding Ctrl
Return key to close path
F fill bounded areas. Select the area symbol, then click on the white space.
Ctrl+F Fill/create border
Ctrl+G switch symbol
D duplicate
Ctrl+D switch dash direction
C connect path; U unify areas
K cut object. Cut lines: click, or click-and-drag to remove the marked part. Cut area: select and draw a cut line. Start & end at object boundary.
H cut free form hole