Complex sentence: In the early stages she was positioned as high as 41st until crashes and punctures caused her to miss the time limit and be excluded from the official race, but her presence had generated so much publicity that the organisers allowed her to complete the event.
Split into simpler sentences: In the early stages she was positioned as high as 41st until crashes and punctures caused her to miss the time limit and be excluded from the official race. However she generated so much publicity that the organisers allowed her to stay in and complete the event.