Unable to prepare mApp for distribution


We have an issue whereby one of our customers are unable to prepare a mApp that they are creating for distribution within there UAT environment to deploy onto their Prod instance (Minor changes that they wanted to apply within one of their Business Objects).  They originally reported the issue except she was unable to take any actions at all when selecting the Create a mApp option from within the Admin Client.

We had her remove the <mergeinstlist> from within the BusinessObjectDef (Customer - Internal) in the Definition Editor and they were able to begin Loading the mApp but when they select Prepare mApp for Distribution, the following error message appears


Has anyone seen this issue before?  They are currently running on version 8.1.2.