The Preferences menu can be accessed from the main panel's hamburger menu > Preferences…
Penpal is localized into Chinese, German, Italian, Japanese, Portuguese, Russian and Spanish languages. Select your preferred language in the dropdown.
Default tab and Default space will preserve your choices across sessions in After Effects.
You can adjust the next four settings by clicking on the sliders or the numbers:
Handle Size determines the size that points and tangent handles display in the panel. On high-DPI screens you may find that even numbers work better than odd.
Directional arrow position moves the arrow that appears on the first segment of each path.
Snapping distance sets the distance from an element that your cursor needs to be to snap to it.
Stroke size sets the width of paths in the panel.
Show all tangents of open paths - the in tangent of the first point and the out tangent of the last point on an open path have no effect on it's appearance. If you disable this checkbox those tangents are hidden, until the path is closed.
Show tooltips can be used to turn off the tooltips.
Use relative tangent values - tangents are treated by After Effects expressions as being relative to their parent point, eg. a tangent with value [0,0] is a zero'ed tangent. Disabling this toggle will make Penpal use absolute tangent values, in the same co-ordinate space as points - so a zero'd tangent will have the same values as its parent point. This setting has no effect on your paths, but it changes the values you see and edit when you double-click on a tangent.
You can set the value of points and tangents numerically with Penpal
Double-click on points to set their value numerically
UI highlight color - the color of selected elements in the canvas.
Snap guide color - the color of snapping indicators.
Contextual menu You can disable the data options in the context menu if you prefer.