We are aware of the review. It is thorough and provides a lot of good information that will be helpful to the developers of the systems evaluated. As the authors state with regard to an earlier review done by the Commonwealth of Learning, evaluations take place within a particular context, and they have to be viewed through a filter that takes into consideration any biases that may be created as a result of the reviewer's needs, purpose, or preconceived opinions etc.. The same is true for this particular review.
see:
https://eduforge.org/docman/view.php/7/7/Shortlisting%20of%20LMS.pdf
I don't know why they would have "serious concerns" over the authentication mechanisms, or even what they mean by that. Authentication in ATutor is adaptable so if you want a particular function password protected you turn on authentication. If you want is public or open you turn it off. Perhaps they were referring to the publically accessible content directory, which has since been corrected.
We are also well into the development of ATutor 1.4, with the 1.4.2 release only days away. Many of the issues raised in the review have been dealt with in releases after 1.3.3. so you should consider the review somewhat dated.
While we were able to use the review to make improvement to ATutor where they had identified weaknesses, some of the findings are somewhat misleading. For instance they state that internationalization is weak, and identify this as a barrier to developing a system to offer their Mouri based courses. There is no reason why ATutor could not include a Mouri translation. They've also stated that ATutor has poor interoperability. In fact ATutor is the only system that provides interoperability of content. There are other such inaccuracies. Regarding modularity, in the introduction to ATutor they stated that ATutor is modular in design, though further into the review they stated it was not. ATutor is working toward a modular design, though it is has not been around as long as moodle has so it may not appear as modular. We're working on it. The ATutor base application had to be well established before we moved into module development. Only recently have we opened the source code to public developers, after first establishing a strong base on which others can develop. The ACollab groupware addon for instance is the first significant module created for ATutor. Adding new functionality onto ATutor is not a problem, and we fully expect many such addon modules to emerge as ATutor matures.
My question to you is, what is it about moodle that you would like ATutor to be "more like", keeping in mind the different philosophies of each system?