I have 15 jos section and more than 1500 jos categories. Can I import all the categories and sections to K2?

AFter installing K2 Click the import Joomla
Be sure to only do this once.
Sections will become categories, categories will become subcategories, and articles will become items

1. Is it possible to terminate the process while is doing the import? I mean if it has timer to stop the import and for so long categories will not have enough time to end the process.
2. Also is it a problem if I have categories with the same name but in different sections? Will the K2 mixed up?

I dont dont think its possible to stop the process while its import gracefully, so i wouldnt try that. Im sure there is a ssl kill command that would work but probably cause problems. I dont know why you would want to interupt it anyway.
2. I would guess that k2 import goes first to the category, gets its subcategories and then goes on to the next one. OR it gets all the sections and then puts the sub categories where they go. I think if you look with phpmyadmin you will find a category id and probably a parent id which makes the names really irrevelant to the computer. (i havent looked)

Ok. I ll check it also.

A blank page indicates an error.
Joomla - Global Settings - Server Tab - Turn error reporting on highest
Try again and see if an error is generated on the blank page and report back.
You may end up with multiple entries in your tables and have to clean them out once you get the error figured out.

Now check the information tab of K2 and see what is says mb_internal encocoding on the left hand side...
Check with your host if its turned off.