The Settings panel opens from Settings on the toolbar. What you set there is Labeljoy's, not a document's: it applies to every document, and it's saved as soon as you change it.

Settings
Language	The language of the whole program, each listed in itself. It changes at once, no restart.
Default number and date format	Which country's way of writing numbers and dates the placeholders use when theirs is Default format. Default format here is your computer's own. See Number and date formats.
Units	Inches, centimeters, or Both, where each document keeps its own - see Measurements and units.
Rulers	Which sides of the work area have rulers: All rulers, Vertical only, Horizontal only, Left top, Right top, or No rulers.
On startup	Show home screen, the home screen; Restore last session, the documents that were open when you closed Labeljoy; or Load default layout, a new document from your default template. Open Labeljoy by double-clicking a document, and that document opens instead.
Snap to grid	Whether elements snap to the grid while you move or resize them with the mouse - see Moving, resizing and rotating.
Tooltips	Whether an element's or a label's name pops up when you rest the mouse on it. It starts off.
Page numbers	Whether the number of each page, or label, is shown above it on the work area. It's never printed.

Activation says whether this copy is a Demo or which license it has - Flex, Business or Enterprise - and is where you type an activation code or deactivate this computer - see Demo, activation and Care+.

Network settings
Use proxy	Only if your network reaches the internet through a proxy - your IT department will know. Then URL, Port, and, if it asks for them, User and Password. A saved password shows as dots: type over it to change it, or clear it.
Method	How the proxy checks who you are: Default method, NTLM, Digest, Kerberos or Negotiate.
Protocol	The secure protocol for connections: Default protocol lets the system choose, which is right almost always; or TLS 1.0 to TLS 1.3.
Test connection	Tries the settings, and says whether the connection worked.

Themes and Advanced
Theme	System follows your computer's light or dark mode; or always Light, or always Dark.
White pages on dark theme	Only with the dark theme: keeps the pages white on screen, as they'll print. Off, the grays are inverted on screen - black text shows white - and a note under the switch says so. Printing and exporting aren't affected either way. It starts on.
Advanced	Closed at first: click it for the three below.
Hardware acceleration	Draws the work area with the graphics card. It starts off.
Restore hidden messages	Brings back every message you hid with Hide this message.
Open log folder	The folder of Labeljoy's log files - useful when support asks for them.