The last two versions of SONAR (Lexington and Manchester) seem incompatible with Eighty Eight Ensemble 2.5 (x64) on my system (Windows 10 64-bit, i5 3550, 8 gigs of RAM).  SONAR crashes every time I try to load the plugin.  Eighty Eight Ensemble 2.5 used to run fine in SONAR on my system before the Lexington update.
 
Are there any users of SONiVOX's Eighty Eight Ensemble 2.5 (x64) that can share their experience with the current version of SONAR?  Eighty Eight Ensemble 2.5 is a great piano plugin and I'm disappointed that I can't use it anymore in SONAR.

Hi. I do not have the 88E, but have you tried to roll back to an earlier release? Could be worth a try.
All the best.

As a workaround, maybe try the 32 bit version.