There are two ways of typing pinyin in Chinese. One is to display accents over the vowels to denote the tone of that syllable, and the other is to represent those tones with numbers at the end of each syllable. I prefer the first of those two and I used bulk upload to upload words that use that kind of pinyin into my course. Some of those words must have been present in other courses because those ones have more columns filled out. In these cases, they overrode the pinyin that I had typed and used the pinyin that existed in the other course. So, instead of displaying the pinyin with accents on the vowels, they are displaying the pinyin with numbers after the syllable. This seems like a bug to me.
The course in which this happened is http://www.memrise.com/course/1094612/hsk-si-ji-shu-xie-yu-kou-yu