I have a mid year transfer date, 1st June 2020.
In the migration template for postings I have filled in the below.
Cumulated Acquisition Value = 1000
Accumulated Ordinary Depreciation = -500
In the Transactions tab I have filled in -1000 for Amount Posted* for the journal entry
Then in the Proportional Values tab
Prop. Accumulated Ordinary Depreciation = 500
When simulating the above the error gets raised.