so far, if u have a valid visa then u should be good 2 travel. However, u finished ur opt. so, there might be change of ur status. so,  it is always safe to consult ur immigration advisor at the college before u travel.

Good luck

have your international student advisor sign the back of your i-20 as well. if f-1 visa expired, can apply at us embassy in ktm. check state department webiste for ktm embassy for current visa application procedure.

u r  going 2 enroll ur new community college from fall, right? Then, i guess though it is issued now, it will b valid only after u enroll ur college. However, u already registered ur class also. why don't u consult ur immigration advisor.

you have already completed your masters and also your OPT.  I seriously doubt that you will have easy visa while coming back with your new I 20 from a community college.  anyone will be surprised  and ask why would someone joins community college after masters degree.  if you can get a I 20 for a Phd program, you will have no problem coming back. 

What will be the safest way to travel AAAA as per your opinion. I need to go for the health check up. It's the main purpose of travelling. Should I study one semester and travel in december. Is it ok if I provide them the letter from the college that this person is travelling for health checkup providing the health documents that I have here in US. What are the other alternatives? Thanks in advance.