LTSVP

If I have a 1 year LTSVP and also from a country that does not need a visa in advance of arrival...

I am allowed to exit and re-enter (for a short trip) Malaysia as long as my LTSVP is valid?  I don't have to stay in Malaysia for the full year and the pass expires if I leave...?

Your question is somewhat weird. A LTSVP visa is not a prison sentence but just a means of staying legally in Malaysia for the prescribed period of time. Leaving and returning during its vailidity is of course OK. However, if you are married to a Malaysian check with this group https://www.facebook.com/FSSGMY/