ID:35051 Register "<name>" from post-fit partition "<name>" was packed with I/O logic on an earlier compilation but has additional connectivity in the current design which makes the packing illegal.

CAUSE: The specified register was packed with I/O logic when the specified partition was last compiled. Subsequent design or assignment changes made the I/O packing invalid. This error may happen when you use empty partitions to optimize a single partition in isolation. The Fitter may identify additional register packing opportunities when the partition is compiled in isolation which would not be legal in the full design.

ACTION: Recompile the specified partition. To prevent the specified register from being packed, create an Auto Packed Registers assignment with an Off value to the specified register.