Tax Ramifications for Profits, Loses and Withdrawals for a Limited Partnership?

Hi, I have a few questions about tax ramifications for profits, loses and withdrawals for a Limited Partnership?

For information purposes, I "contributed" the assets, which consisted of (NYSE traded) stocks), to fund / to start-up, the LP

Question: what cost/what value, do I place on these assets (i.e. the stocks)? The cost that I originally paid or what they are valued when I transfer them into to the LP?

I believe that I can repay myself the cost (or the current value) of the stocks and the next Question: I would also like to know if their is any tax due when I repay myself?

Lets assume for the purpose of this discussion that the stock is determined to cost (valued at) $1,000, the LP subsequently sells the stock for $2,500 and I withdrew $1,500 from the LP.
Question: how do I treat the $1,500 for tax purposes?

I believe that the $1,500 profit is considered a Capital Gain and will flow-through and be reported on my personal 1040 tax return?
I also believe that their will be no tax consequences for the repayment of the $1,000 capital contribution that I made but am not sure how to treat the additional $500 that I withdraw?
Question: is the $500 taxable and if so, what do I categorize this payment as (where does it appear on the K-1)? Also, at what tax rate do I pay of tax on the $500 on my 1040, ordinary income or (something else)???

Thank you for in advance your help,
Bob