Powering a constant current strip with a constant voltage supply
You typically would not use a CV/CC supply for this DMX board.
I would use the Meanwell LRS series CV supply. 
If it works, everything is okay as the Meanwell's output will not exceed 48V.



So you are saying that the constant current strip will run from a CV
supply?

The CV power is connected to the V+ and V- terminals. 
It is my strong assumption that the DMX device has the CC circuitry.  



Will dimming by PWM reduce the current within range so that it is not
damaged?

The current is determined by the DIM+ and DIM- terminals.
You must never allow the DIM voltage exceed the max current of the strip.

I am not familiar with this DMX device so I cannot give you assurances that it will not burn your strip.  Also I know nothing about the strip.  It does seem particular to me that a strip would use only 40-60 mA.
Using a 5 amp driver seems a little mismatched.

If you are only looking to dim the strip you may want to eliminate the DMX device.
You need to describe your application better.  
Post more info about the LED strips and what you want to do with them.
Why are you using a DMX device?
How many strips?
DMX is typically used for complex stage lighting.