Thanks for your help. I'll try your recomendations. Attached is the archive with a manual save.

Quest-Divide and conquer-Can't complete dialog with Milbert Foxhand to acquire the quest due to persistent crashes to desktop when Milbert finishes talking.

The mistake is already in your save that you have uploaded here. I guess one of your mods caused that (Enderal gameplay overhawl?). The horse you will only get back if you load a former save. But you could still "save" your donkey. Open the console, mark the donkey and type in a resurrectactor . Co...

could you upload a savegame? You found it in ...\Documents\My Games\Enderal\Saves , we'll need the -.skse and the -.ess-file of a manual save (no quick- or auto-save) pack them to a rar or zip archive and attach them to a post here, we'll take a look at it then. :) PS: Is it possible your horse die...

The horse flute, the one able to call both the donkey and horse only calls the donkey. Is there a solution?