SignalTap II sample clock timing violation

SignalTap should be running on the same clock as the signals you're sampling, in which case it's fully synchronous transfers and there's no need to oversample. (I've never heard of oversampling with SignalTap when grabbing from other, asynchronous, clock domains, but imagine it could work. Still hard to read the data since it's not just what you capture, but how it aligns with other signals, which you can't fully count on...)