Employment pass - DP10 DP 11 (Kuala Lumpur)

Hi guys,
I've been here for two years and am in the process of getting my work visa renewed. My previous visa expired in September. I have been told that my DP10 has been approved and that I'm waiting on the DP11 being processed. I'm not really sure what these are...I have a letter from immigration saying that my work permit is being processed. What I want to know is if anyone has travelled outside of Malaysia whilst their work visa is being processed? Will I have problems at immigration or will this letter I have been given be sufficient?
Thanks in advance!
Stacey x