I’ve found a few places in Synfig with a little confusing or misleading labelings;
In the Preview options it says zoom but what the option does is not zoom, it’s resolution/quality. Suggesting to rename to quality.
Layer panel, menu it says remove layer. There’s also remove layer from group where the layer is removed from a group but still is kept in the project. Remove layer deletes the layer from the project. I suggest rename the option to delete layer which suggests a more definite removal than remove.
In render settings it says Use current frame. For what? Could be relabeled to Render current frame only or something similar for clarification.