I am facing the same issue,I tried doing whatever you have mentioned in your comments,But while giving permission to the content-authors group,i am getting the error: No tree at /path_to_text_component.If you have faced the same issue,Please let me know the solution Thanks.

Whenever i am uploading image in the 6.3,DAM update asset workflow  is getting failed.Its throwing the below mentioned error.Failure Message: Process implementation not found: com.day.cq.dam.s7dam.onprem.process.S7damExtractImageInfoProcessStep:Dynamic Media On-Premise extract image info.com.adobe.g...