I bought Dex a few days ago. I installed it, and played it for a while the first night. I got really into it and was super looking forward to playing more. Last night I tried to load it and it didn't load. I uninstalled/reinstalled. No dice. Tried installing on another HD. Still not loading. I'm running Xubuntu 18.04, drivers up to date.

When I run it from a terminal with $sh start.sh I get this:
start.sh: 6: start.sh: Bad substitution
start.sh: 8: start.sh: source: not found
start.sh: 11: start.sh: get_gameinfo: not found
start.sh: 12: start.sh: get_gameinfo: not found
start.sh: 13: start.sh: get_gameinfo: not found
start.sh: 43: start.sh: define_option: not found
start.sh: 44: start.sh: define_option: not found
start.sh: 47: start.sh: standard_options: not found

I don't get why it worked once and then stopped working after. Any help, please?