Thanks for sending me the test case.
I found that the call to AddCross and RandCovPoint had a cross product of 6 items, however, the call to ICover only had 5 items. When I changed the test code and stubbed out the transaction procedure calls, it ran to completion without errors on my install (Windows 8.1, RivieraPro 2015.02 64 bit).
As a side note, ICover minimizes the amount of error checking that it does. It is always in the critical path of execution. It is a tricky problem. Sure would be nice to have the error checking in the code for a debug simulation, but not have it in the code for a mature testbench that is running regressions.
I should also note that I tested on the 2015.06 release.