The Contractor submitted its XER file for its updated programme using P6 Ver 7. I imported the file using P6 Ver 18 and its showed that the Overall progress percentage is not the same. Contractor's update is showing 95%  and my import is showing 91%. I investigated the updated programme and found that some of the activities under Engineering and Mobilization WBS were having a % Complete Type of "UNITS" and it appeared that the progress % on these activites having this setting do not roll up to the WBS summary and similarly to the Overall progress percentage. Why and what is the reason for this issue? was it because of different P6 Versions or there are some settings that i need to adjust/change??

In the morning after, i managed to find a friend's Laptop having a P6 lower version (P6 Ver 8.3). So, I immediatley set up the import process and much to my relief, the progress percentage match to that of the Contractor. However, another issue came up. The Contractor's Overall BL Labor Units is 810,966  and on my import on P6 Ver 8.3, it was showing 81,096. 

Is the software crazy or i missed some settings during the import process or in my user preference or admin settings?

Is there any way to circumnavigate on this issue? or a practical solutions based on your experience?

I appreciate your kind help. Thank you.     

Bong Yagahon