Could you elaborate your situation. It's not clear for when were you out of status. Did you leave US within 5 months of being out of status ?
To my understanding, there is nothing like getting re-instated at kathmandu or at port of entry. If your Visa is valid and you have a new I-20 you can travel to US. You will be entered as a new student in the system (since your new I-20 will hold a new number for you in the SEVIS system), although the system will show your past record. The people at port of entry will know that you had problem with your status.
My concern is IF you were out of status in US for more than 5 months and then left to Nepal, then that might be a problem.
Be prepared you will be called for questions at the port of entry.
My experience, I was out of status, I stayed here for 5 months then left for kathmandu. I stayed there for around six months, got bored, applied for new I-20, then came to states. I applied for a new visa, and it was really easy. I wonder if at US embassy to kathmandu, if it even shows in the system that you had problem with your status, cause they did not ask me ANY question about my earlier status problem, although I was ready to explain them.....
However, at the port of entry, it does shows in the system, and they make you go to a different office, which looks like visa interview room we have in ktm...then they asked me few questions...i explained them of being out of status for working over the specified time in the college........and then seemed like they didn't had any problem with that....they were like, "college could have just reduced your hours for the following week, they didn;t had to put you out of status.."....
Well anyway, good luck with your venture......