General Description: There is a bug in the Virtex Binary Counter in which the logic associated with SINIT (Synchronous Initialize) is not generated when you generate the counter with a "Count To" value specified. (Before you can specify the "Count To" value, you must first activate the "Restrict Count" option in the Binary Counter GUI.)
As a result of this bug, the Counter does not get initialized with the user-specified initial value when SINIT is asserted. The bug is actually in the implementation netlist, so the symptoms can be observed during both post-NGDBUILD and timing simulation.
As a workaround, regenerate the core with a LOAD input and use it to load the desired initial value from the L input instead.