Faenrir: What a condescending terrible answer to your customer.
That's not it. The animations are very choppy because of the sounds. Not sure what the issue is but the original game on original hardware was not choppy like this.
If you disable the sound, the issue is gone and the animations are much smoother. Slow, yes, but not choppy.
I'm guessing some improvement could be made to the dosbox settings but haven't fiddled with them.
Try a Dosbox fork like Dosbox Staging or X. Actual DOSbox hasn't updated seriously since Barak Obama was in office. And GOG uses
that version. Unlike Staging, whose latest release candidate was January 21st, this year.
Chances are, they've fixed whatever the issues are, given that they implemented proper "as a DAC" support.