Will this lock in the on position and can it be used with the colins coping foot?

The switch has on/off positions, so yes it is possible to leave it in the on position.We cannot comment on compatibility with the Collins foot. We do not have the non-Festool compatible version of the coping foot in stock to test it. We would recommend contacting Collins directly, but since this jigsaw model is brand new and we only began receiving inventory today, they will likely have no way to verify compatibility.We tried contacting Collins, but their phones have been busy this morning.https://www.collinstool.com/contact-us/