MAS will not give you a reply unless they are interested in your application
To be fair, the vast majority of Malaysian companies won't bother with replying an initial application, either.
From what I've seen the time between application --> psychomotor varies wildly from a few weeks to months.
Psychomotor --> MISPA, 1-2months
MISPA --> Interview, 1.5-2.5months
Interview --> Medical ... don't know ;o)