ae-scripting-expert

Wrap code in an IIFE to avoid global namespace pollution, use var instead of const/let for ES3 compatibility, and wrap operations in app.beginUndoGroup/app.endUndoGroup. Remember AE collections are 1-based, so the first layer is comp.layer(1).

Check whether thisObj is an instance of Panel; if so use it directly, otherwise create a new Window of type palette. Build the UI, call win.layout.layout(true), and only call win.show() for palette windows, not docked panels.

File writes fail when the 'Allow Scripts to Write Files and Access Network' preference is disabled. Check it via app.preferences.getPrefAsLong on Pref_SCRIPTING_FILE_NETWORK_SECURITY and prompt the user to enable it before file operations.

Navigate from the layer's ADBE Root Vectors Group into an ADBE Vector Group, then its ADBE Vectors Group, and add an ADBE Vector Shape - Group whose ADBE Vector Shape property holds the Shape object with vertices and tangents.

Shape vertices are defined in layer space, not composition space. Convert composition coordinates by subtracting the layer position, dividing by scale, and adding the anchor point before assigning vertices to the Shape object.

app.settings values are limited to roughly 1999 bytes and can throw on larger data. Store only booleans, numbers, and short strings, and call app.preferences.saveToDisk() after saveSetting to persist values.