1) You can define your own chapter marks and have one at the end of your movies.
2) Only 40 titles in ver 2.5 -
I'm building another (completely different) version of multiAVCHD that will have support for as many titles as one may need, along with much more intuitive interface.
Menu has nothing to do with title count so it is not that easy to add more titles. The major problem comes with the Non_compliant titles that require another program fragment in movieobject. At this point multiAVCHD supports 80 titles but only 40 available (40 compliant or 40 non-compliant, or mixed but up to 40).