I recently experienced the below error while deploying a Case Manager solution.
FNRPA0032E The solution cannot be deployed because the Process Engine configuration document could not be imported. See the following error: Failed API_TransferConfig
There may be various reasons for the error, but it was a data issue in my case. Analyzing the Process Engine logs (pesvr_system.log, pesvr_trace.log) revealed that one orphan work item (that was terminated) was lingering in the system and was preventing the deployment. The work item was deleted and the deployment was successful.
Hope this helps!
RK 