I learned that "dümpeln" or "dahindümpeln" comes from low German "dümpelen" where in the sailors language it means that a boat is bobbing around not moving forward. Today it may also be used when work does not proceed in the desired speed
Dieses Projekt dümpelt seit Monaten so dahin.
Is there still a regional difference in the usage of this word? Is it also used (or understood) in southern regions of Germany, in Switzerland, or in Austria?