In brief, BBS-Advert is simply a MAXs Door that displays adverts/bulletins.

 PERMSSN    UID  GID    PACKED    SIZE  RATIO     CRC       STAMP          NAME
---------- ----------- ------- ------- ------ ---------- ------------ -------------
[generic]                  831    3305  25.1% -lh5- c24f Dec 14  1999 bbs-advert/adds/BBS-Advert.02
[generic]                 2700    7980  33.8% -lh5- 7023 Dec 14  1999 bbs-advert/BBS-ADVERT!
[generic]                 1137    3200  35.5% -lh5- 2038 Dec 14  1999 bbs-advert/BBS-ADVERT.GUiDE
[generic]                  220     465  47.3% -lh5- edaa Dec 14  1999 bbs-advert/BBS-ADVERT.GUiDE.info
[generic]                  491    1096  44.8% -lh5- 212b Jun 15  1996 bbs-advert/BBS-ADVERT.origin
[generic]                   64      64 100.0% -lh0- 948b Dec 14  1999 bbs-advert/BBS-ADVERT.prompt
[generic]                  471    1027  45.9% -lh5- 2eae Dec 14  1999 bbs-advert/adds/BBS-Advert.01
[generic]                  491    1678  29.3% -lh5- e2b0 Dec 14  1999 bbs-advert/adds/BBS-Advert.03
[generic]                  389    1614  24.1% -lh5- ec2e Dec 14  1999 bbs-advert/adds/BBS-Advert.04
[generic]                  179     360  49.7% -lh5- 736c Jun 14  1996 FiLE_iD.DiZ
[generic]                  469    1652  28.4% -lh5- 8b03 Jun 14  1996 GREMLiNS.BBS
---------- ----------- ------- ------- ------ ---------- ------------ -------------
 Total        11 files    7442   22441  33.2%            Jul  6  1996