Thanks, I'm glad you like it! The path currently isn't set up to be kept between creating new games, but it's an option I may add in the future.
Regarding the trackpad issues: the software is designed to be used with a mouse, so using one is recommended if possible.
I'm not sure about deleting not working in the Map Editor, I haven't had any reports of that before. Do you have an entity selected in Edit mode when pressing the delete key? As an alternative, you can right-click the selection and choose "Delete" from the popup menu.
Hopefully that helps!