The K-1 doesn't provide any info on your short or long term capital gains/losses; those are handled separately on your Sched. D. If you use Turbo tax for example, all your trading gains and losses can be imported directly from your brokerage company and the K-1's, which usually come in much late,r are handled in a manual entry method. If you have many of the K-1s it is really worth it to get Turbo tax as the program leads you by the hand - step-by-step.
That is incorrect, the K-1 will affect your basis in the company. Turbo Tax will not help you with this issue, you really need to see a professional. There is what we call inside and outside basis. Depending on the buys/sells and what gains or losses you show on your K-1. Trust me, do not try this on your own if you don't know what you are doing or you will probably end up screwing yourself more then this stock has.
MMAB has a Section 754 election in effect, if you bought shares post IPO your inside and outside basis are the same.
As long as you adjust your basis in your shares for the items of income and gain (taxable and tax-exempt) loss and deductions (including nondeductible expenses) when computing your gain or loss on the sale of your shares, you should be fine. It isn't that hard.