I use quite often samples longer than 64 steps, but always sampled by the OT at the same tempo, so if I loop the sample, it wont go out of sync over a longer period of time.
I think that if you have a longer, rhythmic pattern/sample, made outside of the OT, using the looping technique won’t give a good result, it will drift after a while. Even if it was made at the same bpm etc. The length error will add up fast, cumulative.