1) 1) Ideally, one should not call someone who is in the middle of reciting the verses of praise to read in the Torah, unless he is the only Kohen or Levi in the synagogue, in which case one may call him up, and he may even read the verses quietly with the reader of the Torah. (Shulchan Aruch and Mishne Berurah 51)
2) 2) When one is called up to the Torah when in the middle of the verses of praise, if one is near the end of a chapter and can finish it without delay, he should finish it. If, on the other hand, he will delay the congregation by finishing it, he should not finish it and just go in the middle of the chapter. (ibid)
