So it looks like what originally happened was that OpenDune would not start because it could not find dune,cfg in MyDocs/games/DUNE2, and this is because my MyDocs got destroyed. This a guess, though.

Then, running opendune.sh from /home/opt/usr/games, it compains it cannot load the data file. The data file should, I guess, come from /usr/share/games/opendune/data, which has a put_dune2_here.txt file.

To summarize, I think originally OpenDune could not run because of my MyDocs mishap, and now it won't run because the fresh install is not correct.