Is it possible to add auto travel on older version? And how to add it?
Nope, the only option is to migrate to the latest version or do a lot of coding.
Out of boredom, the realization the vision DDA now follows strictly, specially past 0.D, will never be enjoyable again for me, but mostly because of boredom, I ported auto-travel through judicious cherry-picking of the specific PR and necessary modifications to code. Note though this custom less than half-baked fork of 0.D source code includes more than that: no filthy clothes or ahem “biosignatures” among a few other changes documented therein. In this link there is the modified source code, a Linux and a Windows 64-bit binary as zips(plus a mod I’m about to publish here). If you’re running a Mac, you will have to download the modified source and compile it yourself I’m afraid, because it would be pointless to cross-compile something with no way to test whether it will work or not:
Hope this helps and will be of interest to others as well.
Why would you post your fork to google drive instead of github?