"Makeyourowndrinks" Cider smells like sulfur and turned a brownish colour, is this normal?

Sulfur odor is usually a sign of poor yeast heath and/or high sulfur levels in water

Color is change is most likley just yeast in suspension offsetting the true color.

Sulfur odor is usually gassed off during a vigorous fermentation. It's not too late to save it.

Here's what you can do.

1) Right now you need to add yeast nutrients, this should be done before but may not be too late to get yeast going better.

2) if fermentation has slowed, you can add corn sugar and a lot of it. 1lb per gallon will keep the fermentation going and almost double your abv making it more an applewine

3) if extending the fermentation with sugar isn't desired. (higher abv) You can gas off the sulfur by force. But takes equipment. Using a c02 tank, gas stone, and liter per minute 02 regulator. You can apply gas until the oder is gone.

Edit: That recipe and intructions is a little strange. I don't know where to start. It says to use unboiled tap water for most of the fermentation volume. Potable water is not always sanitary and usually swimming in organisms that don't harm us, but makes for a less than ideal environment for fermentation. You would do much better just buying preservative free apple juice and some bakers yeast from a grocery store.

Strong "rotten egg" smells are always subjective ("one man's horrendous stench is another man's garlic"). I have noticed some sulphurous smells when producing "fruit ciders" as well as lagers, although nothing as overwhelming as fermenting KimChi! Sulphurous smells during ferementation are not uncommon or indeed fatal when making cider and many other brews. The term "rhino fart" is often humorously used in this context (have a google for it) The "problem" seems to be due to the specific yeast chosen. Lager yeasts are known to exhibit this aspect of fermentation. Some yeast have high nitrogen requirements which may not be satisfied by the amount available in the apple/fruit must. In such situation's "rhino farts" can occur and give the impression that something is going wrong with the brew. As others have noted this can be alleviated by adding a nitrogen nutrient to the must. However if the cider fermentation is vigorous and in progress then it would probably be best to let it ferment to completion and let it stand until the aroma has dissipated somewhat. The test is in the final taste not in the smell during fermentation. Most malodorous aromas are removed by long conditioning. After fermentation I would let cider stand/condition for at least 12 months - whatever it initially smelt like.

Don't have experience with this specific set, but I made cider few times.

• Sulfur smell is not normal. OK, there are specific ale strains that give it no matter what, but most of the times it means you have wild microorganisms fermenting, or your yeast have problem with lack of nutrient. In ciders, lack of nutrient is a mistake easy to make. At this point, I doubt this can be corrected. Some batches would taste OK in the end, some would not. If it will, it will probably be safe, too. This time just wait and see. Next time add yeast nutrient.

• Some fading of color is normal. Most beverages are bit paler after fermentation, and loss of "color saturation" happens. I don't know where orange came from. I strongly suggest asking manufacturer about that.