Hi! The linux build might be outdated, can look into this for you!
Interesting. Why does this game even need curl?
I was able to get it to run ok (not using the itch launcher) by installing the libcurl-compat package and using:
$ LD_PRELOAD=/usr/lib/libcurl.so.3 ./launch.sh
I'm not sure why the dependency on libcurl exists, but it would be nice to update to work with contemporary libcurl.