Yeah the OC’s website will be completely shutdown pretty soon according to their notice on their website, so this will be the only way to use this after its shutdown completely. The OC said something about it was costing them too much money to keep it live on the web so they’re shutting it down. As far as what’s different, not much is different except for the fact that this is an Offline version and the soon to be dead web-based version requires internet access to use. I made this with the latest version of the website’s code so its up-to-date with the latest web-based version’s features.
Edit: I just noticed you were referring to v0.14.0, and I honestly have no idea if how much was changed from v0.14.0 to v0.15.0, but I do know the code on the GitHub repo had some majorly outdated NPM dependencies that was making the build fail but I was able to solve that and I got it to build just fine after some version conflict investigating.