1. The kernel file can not be opened. But the legacy image was only created to in case the usual GPT disk is not possible.
2. The size of the used stick is unknown so we start with a small 32MiB file system that is expanded at first boot.
The filesystem repair may have been started because you pulled the stick before any data was flushed.
A. Don't be afraid of the installer, you have to select the installation, choose the disk and then being asked twice if you really like to erase the HD.
B. We do use a GPT image. The changes will be used if accepted by the team.
Let's hope the current LE image is upgraded with your updates after some changes 😉