Will this release include achievements like the Steam release? Cheers.

I came here for the same question now that the achievements have been raised as one of the nice features of these re-releases in the interview :)

The game was made in Adobe AIR, and it seems GOG Galaxy SDK doesn't have support for it, so there's no Galaxy achievements. It looks like the dev did try to implement it before figuring out it didn't work:
https://www.exophase.com/game/the-elephant-collection-gog/achievements/

Thanks for the info...

I thought this was discontinued but a quick search showed that AIR found a new home. I can totally understand why they choose that to "remaster" Flash games and also why it may not be supported by GOG (due to the limited, at least as far as I know, relevance of AIR).

If someone more technically minded than I am when it comes to achievements support, I'd be curious to know why it Steam supports it and not GOG. Is Steam SDK, by design, more technology agnostic or is it just a matter of resources and Steam having more people working on it allowing more technologies to be supported?

It's a mix of reasons. Some game SDKs have official support made by the developers of the SDK themselves (like for Visionaire Studio), some are made by GOG (like the plugins for Unity and Unreal), and some are made by the community (like the plugins for Game Maker and Defold). Steam also has little official support but due to it's wide usage, both the community and SDK devs have developed Steamworks support for every engine out there. Galaxy's SDK is only available to devs, so that's another reason it's harder for the community to get their hands on it and make plugins for it.

Thanks (again :) ) for the detailed reply.