I haven't tested a single build for several months (real life...), but It seems that there is another bug present in v2.2, which is similar to ID: 3484430 (https://sourceforge.net/tracker/?func=detail&aid=3484430&group_id=89530&atid=590426).
This time, however the issue was not scanning of archives, but video files - none of the files FROM SUBDIRECTORIES were scanned by mediainfo (v0.7.57, perhaps it's a mediainfo issue?!) or at least the scanning result (audio-video information) was not displayed in the yellow area (column) on the right side.
Tested (for now) with CdCat v2.2, on Win7 x64.
I'll try to make another test on Debian tomorrow.