Actually, *many* of the levelset packages have wrong / obsolete URLs, but are corrected by site redirects. It would be better if the package contained the most current URLs, since they're more likely to remain correct or at least continue to have future redirects to The Next Place.
In the following list, '[NOTES]' shows what I changed to form the (current) final redirect: [S] changed URL schema from 'http' to 'https' [L] changed '/unix/' to '/linux/' [W] added 'www.' [M] migrated from ancient web.archive.org URL to artsoft.org (where most of the rest of the files are from) [R] changed to reflect site reorganization (but -- as previously mentioned, for this one a Wayback URL might actually be better?) After the notes is the URL currently used in the rocksndiamonds.postinst script. The subsequent '==>' line shows the recommended replacement URL. [SL] http://www.artsoft.org/RELEASES/unix/rocksndiamonds/rocksndiamonds-4.4.1.3-linux.tar.gz ==> https://www.artsoft.org/RELEASES/linux/rocksndiamonds/rocksndiamonds-4.4.1.3-linux.tar.gz [S] http://www.artsoft.org/RELEASES/rocksndiamonds/levels/Zelda-1.0.0.zip ==> https://www.artsoft.org/RELEASES/rocksndiamonds/levels/Zelda-1.0.0.zip [SW] http://artsoft.org/RELEASES/rocksndiamonds/levels/ZeldaII-1.0.0.zip ==> https://www.artsoft.org/RELEASES/rocksndiamonds/levels/ZeldaII-1.0.0.zip [S] http://www.artsoft.org/RELEASES/rocksndiamonds/levels/Contributions-1.2.0.7z ==> https://www.artsoft.org/RELEASES/rocksndiamonds/levels/Contributions-1.2.0.7z [S] http://www.artsoft.org/RELEASES/rocksndiamonds/levels/Snake_Bite-1.0.0.zip ==> https://www.artsoft.org/RELEASES/rocksndiamonds/levels/Snake_Bite-1.0.0.zip [S] http://www.artsoft.org/RELEASES/rocksndiamonds/levels/BD2K3-1.0.0.zip ==> https://www.artsoft.org/RELEASES/rocksndiamonds/levels/BD2K3-1.0.0.zip [S] http://www.artsoft.org/RELEASES/rocksndiamonds/levels/Boulder_Dash_Dream-1.0.0.zip ==> https://www.artsoft.org/RELEASES/rocksndiamonds/levels/Boulder_Dash_Dream-1.0.0.zip [SL] http://www.artsoft.org/RELEASES/unix/rocksndiamonds/levels/rockslevels-dx-1.0.tar.gz ==> https://www.artsoft.org/RELEASES/linux/rocksndiamonds/levels/rockslevels-dx-1.0.tar.gz [S] http://www.artsoft.org/RELEASES/rocksndiamonds/levels/Sokoban-1.0.0.7z ==> https://www.artsoft.org/RELEASES/rocksndiamonds/levels/Sokoban-1.0.0.7z [S] http://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/r-structure.zip ==> https://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/r-structure.zip [S] http://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/earth_3120.zip ==> https://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/earth_3120.zip [S] http://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/r-graphics.zip ==> https://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/r-graphics.zip [S] http://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/r-sounds.zip ==> https://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/r-sounds.zip [S] http://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/eem.zip ==> https://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/eem.zip [S] http://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/might_of_elementals.zip ==> https://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/might_of_elementals.zip [S] http://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/mod_secret_command.zip ==> https://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/mod_secret_command.zip [S] http://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/natural.zip ==> https://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/natural.zip [S] http://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/world_of_amoeba.zip ==> https://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/world_of_amoeba.zip [S] http://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/r-old.zip ==> https://www.artsoft.org/rocksndiamonds/levels/richardkleber/RnD/r-old.zip [M] https://web.archive.org/web/20110101150015/http://home.freeuk.net/jamiecullen/zips/ww_v1-0.zip ==> https://www.artsoft.org/rocksndiamonds/levels/jamiecullen/zips/ww_v1-0.zip [M] https://web.archive.org/web/20110101150015/http://home.freeuk.net/jamiecullen/zips/wg_v1-0.zip ==> https://www.artsoft.org/rocksndiamonds/levels/jamiecullen/zips/wg_v1-0.zip [M] https://web.archive.org/web/20110101150015/http://home.freeuk.net/jamiecullen/zips/wf_v1-3.zip ==> https://www.artsoft.org/rocksndiamonds/levels/jamiecullen/zips/wf_v1-3.zip [M] https://web.archive.org/web/20110101150015/http://home.freeuk.net/jamiecullen/zips/es_b_v1-2.zip ==> https://www.artsoft.org/rocksndiamonds/levels/jamiecullen/zips/es_b_v1-2.zip [M] https://web.archive.org/web/20110101150015/http://home.freeuk.net/jamiecullen/zips/ese_v1-1.zip ==> https://www.artsoft.org/rocksndiamonds/levels/jamiecullen/zips/ese_v1-1.zip [R] http://www.jb-line.de/hp/rnd_jue-v8.zip ==> https://jb-line.de/rnd17/rnd_jue-v8.zip Applying these changes makes the downloading process look much less messy (and somewhat faster, as the redirects are a bit slow). Also, as the existing 'rnd_jue' URL fails (not just redirects), it breaks the postinst. The game ends up playable but I think 'AB Levelsets' (the last one, comes right after 'rnd_jue') never gets unpacked.

