By just uploading your unmodified dll.xml here, you wouldn't obivously messed it.
Instead, you might risk doing so, by renaming it to a .txt file, because xml is not a text file, and it might change when being transmitted because of this. We have configured the forum software to accept XML files just for this reason, so users can send their XML files without as they are, without having to changed them.
In any case, if that dll.bak.txt is a copy of your dll.xml file, there's nothing wrong with it so, and it includes both our Addon Manager section and the PMDG section so, at least those two modules should work.
I've noticed you have the Addon Manager entry as the last line, which means you are not using the current version of our installer because, it has been several months we put our line as the first line, because there are compatibility issues with other modules (like Audio Environment, which you ARE using!) that don't work if they are loaded before the Addon Manager.
I've made a merge of your two files, putting our line at the top, which is what our current installer would have done anyway. I don't see any entry for Level-D, so I guess the problem is because you have sent me an XML backup made before installing the Aerosoft CDG, which might have been made when the Level-D module wasn't there yet. You should have a backup made by our installer instead, which should contain the Level-D section.
In any case, I suggest upgrading our installers because, since I see only a PMDG entry in your current DLL.XML file, I suspect the issue might have been caused by a PMDG installer instead, which is known not to properly process XML files, relying on linebreaks as they were text files, which is not correct in XML so, their installer can get confused if a section don't use linebreaks, which is what happens normally when adding/removing entries using the standard MS XML parser.
We added an additional feature, to reformat the XML file at the end of the installation in the current version of our installer, so other installers will not get confused by XML files with missing linebreaks (they shouldn't, because XML without linebreaks is 100% legal XML!!), and they don't corrupt the file themselves, if they are run after our own.
