roxygen answered your question: Arab Student Union hosts Doctors for Dr. Ron Paul

What particular stances contrary to Arab American interests and Arab Americans alone?

I never claimed they were Arab-American issues alone. Arab-Americans do not comprise a discrete group that is disconnected from the rest and towards whom Ron Paul is particularly antagonistic. Rather, Arab-Americans live lives that negotiate between various pressing issues, and these issues are ones which I find Ron Paul does not address satisfactorily. That is not to say that these are uniquely Arab-American issues.

Briefly and informally, some of his positions which I think are problematic somewhat particularly to Arab-Americans are:

• his objection to the Civil Rights Act—even if his objection is merely that it is mandated federally. Arabs and other minorities face discrimination and racial profiling despite having such legislation in place. Ron Paul construes this type of legislation as a “massive violation of the rights of private property and contract.” Presumably, the right to be free from discrimination is not as paramount of a concern as the rights of private property. Whether or not this legislation is effective (I think to some extent it is, and he thinks it is not), he disagrees with it not based on its efficacy but rather on principle. 
• though he believes in non-intervention, this is not because he is just a kind pacifist who thinks Americans should mind their own business. His position on the Panama Canal illustrates such a tension. He rejected the Darfur Accountability and Divestment Act. His emphasis is not on non-intervention but rather on not interfering with the free market. Presumably, intervention is outside the domain of the sovereign free market, but an act focused on accountability is a constraint on free market practices. His non interventionalism is arguably harmful when you consider that it represents a sort of “America in a vacuum” model. America’s business practices, at the very least, “intervene.” But he is disinterested in precluding that type of intervention. He also thinks we should withdraw from the UN.
• contrary to popular belief, he did not vote against the NDAA. He merely did not vote, and later supplemented a position against it. I will not speculate as to why this was his decision, but he is no better than Obama with regards to protecting the rights of citizens against unreasonable search and violation of privacy. His later advocacy for its repeal as a private citizen does not absolve him of his inaction as a public servant. This is obviously an issue for Arab-Americans and Muslim-Americans. Additionally, his position on issues of the right to privacy are precarious aside from his NDAA non-vote.
• issues of immigration are very important for Arab-Americans, and so his immigration policies are problematic. He is against birthright citizenship. See also: his position on the wall with Mexico. Yes, we do not share a border with Syria or Algeria, but I think one has some latitude to extrapolate from this instance a greater theme of his immigration policy.
• he is a racist