Let me re-iterate the issue:
1. I have the same INSTANCE running on the virtual box
2. I have two databases restored on that box next to each other
3....

Many thanks for the wonderful picture DesNorton, but again - my actual number...

Actual number of rows is very similar (within 10% difference) Something is the counters is giving me the feelings that buffer read is involved but what and how - no...

That is another interesting observation - the actual number of rows :
EXEC sp_spaceused 'ActivityInstance'

ActivityInstance    217136         59520 KB    52888 KB    6312 KB    320 KB
ActivityInstance    219209     ...

Sure : Here is the set of actual execution plans per your request. Many thanks Michael for your time

That is a freshly loaded DEV / STG Box all statistics are fresh and indexes are rebuilt , buffers are cleaned and cache is free before each execution since that...

And here is the SHOWPLAN_ALL txt format

Sure - here they are in XML

 Many thanks SSC Guru for your reference. Yes these objects (physical tables) even they are fairly alike...

The ObjectVersion value of the cube is an internal numeric value that is used for isolation management and cannot be changed. We are using the hard coded version for attach...

Just FYI

I am using SSAS 2008 SP1 CU6 Build 10.0.2757