The file globs define a set of files we're looking for on the CD. If a file is found and has no associated patterns, then we consider that we have found a match.
Otherwise we then proceed to scan the content each file matched by the glob using the corresponding regular expressions. If we find matches for all the specified patterns, then the CD is a match.
The advantage is that a carefully chosen combination of file globs and regular expressions lets us cut through all the CD variations. It also does not require the author to get his hands on all the CDs to get something that will work in the majority of cases.
It requires a good look at the content of the application CD to identify how to identify it; and then to write file globs and regular expressions that work. But we also require authors to be able to write globs for the InstalledXxx properties and quite a few others.