Here is an update. For the merge i was missing these files: DBM_HA+DG_Patch.esp (Legacy of the Dragonborn Patcher (Dragonborn Gallery))DBM_IA_Patch.esp (Legacy of the Dragonborn Patcher (Dragonborn Gallery)) I managed to extract them manually from the archive Legacy of the Dragonborn Patch Collection v16.11.5 (not v16.11 since it is no longer available) Now with merging DBM_ArtifactsOfBoethiah_Patch.esp i get this error:
[00:00] Checking for Errors in [07] DBM_ArtifactsOfBoethiah_Patch.esp
[00:00] [REFR:0700590D] (places [06392D96] < Error: Could not be resolved > in GRUP Cell Persistent Children of DBM_test "Dragonborn Gallery Hall of Heroes" [CELL:06125EE6])
[00:00] REFR \ NAME - Base -> [06392D96] < Error: Could not be resolved >
[00:00] [REFR:0700590C] (places [06392D95] < Error: Could not be resolved > in GRUP Cell Temporary Children of DBM_test "Dragonborn Gallery Hall of Heroes" [CELL:06125EE6])
[00:00] REFR \ NAME - Base -> [06392D95] < Error: Could not be resolved >
[00:00] fearstruckDISP [REFR:0700590A] (places [06392D90] < Error: Could not be resolved > in GRUP Cell Persistent Children of DBM_test2 "Daedric Exhibit Hall" [CELL:061263AD])
[00:00] REFR \ NAME - Base -> [06392D90] < Error: Could not be resolved >
[00:00] [REFR:0700590B] (places [06392D8F] < Error: Could not be resolved > in GRUP Cell Temporary Children of DBM_test2 "Daedric Exhibit Hall" [CELL:061263AD])
[00:00] REFR \ NAME - Base -> [06392D8F] < Error: Could not be resolved >
[00:00] [INFO:060DE730] ('After your defeat of the Dark Brotherhood, the Emperor was informed of your great deed.' in GRUP Topic Children of DBM_GoldBrandDeliveryPOM1 "Very well, let's hear it." [DIAL:060DE72F])
[00:00] INFO \ VMAD - Virtual Machine Adapter \ Scripts \ Script \ Properties \ Property \ Value \ Object Union \ Object v2 \ FormID -> [06392D9E] < Error: Could not be resolved > I have yet to figure out what this means and how to resolve it. Also posted a bug report on the nexus mod page just in case. Any ideas?