Some mutations could have a chromatogram signal lesser than the reference one. This situation very often appears if the mix of cells (healthy and oncological) has been being analyzed. That means that the mutation signal could be different (due to a different concentration of oncological cells in a sample).
These kinds of mutations we call Alternative mutations.
You can zoom in and zoom out by the corresponding toolbar buttons. To reset zoom use the Reset zoom button. To increase/decrease peaks height use the corresponding buttons.
You can change font by Appearance–>Change characters font context menu item or by the main Actions–>Appearance menu item.