The Preview Edition runs only on vB 3.6.x.
But the Professional Edition runs with vB 3.5.2 and newer.
Please try the following to install vBStatistiv Preview Edition in vB 3.5.2 or newer (this has not been teste --> first create backups!):
Try to delete the following parts out of file
product-vBStatistic Preview_english.xml:
In version 3.6 (and 3.62) there were changes in some structures in the product xml file. Amongst other changes you can now define an order of execution for plugins. Ordering is set via table entry
executionorder.
vB table
plugin doesn't contain this field in version 3.5 so there may be errors with the non modified version of vB Statistic Preview Edition.