The game got released on Steam and has a bunch of fixes/changes:
https://steamcommunity.com/games/3843540/announcements/detail/507336391076611393

Will the GOG version be updated, too?

I wish

Well... "Demon Stone" re-release is already on GOG as an "Alternative version", so the chances are high. Maybe some day soon...

Its on here as a beta channel and only thru galaxy not offered as a offline installer.
So beta channels are basically drm launcher only games.

It is offered as an offline installer among extras, labeled Alternate Version.

it is published by SNEG which means that it should be available for gog.
though it seems to already be available.

it is already here. though the offline installer is zipped and needs to be unpacked.

i tested it myself and it fixes a lot of stability issues. i had a lot of crashes on the bigger maps before but, now i have none. i tested it in windows 7 and 8.1 and it works in both. though i had to create new firewall exceptions, as the firewall thinks that the executable is a new file.