FIR Filter Fault

I am trying to implement a FIR filter in my QSYS design but I cannot insert the megafunction in QSYS due to error I cannot resolve.

"Error: child process exited abnormally".

I am using quartus 12.0 sp2.

I did manage to implement it in the design once but when I went back to edit it the error appeared again.

All help would be appreciated.