IMO, pick up a dedicated controller meant for RGB, you are turning a mole hill into a mountain trying to have your APEx handle the three color channels.
regardless, here is what you need.
https://www.amazon.com/Dimming-Cont...ocphy=9003805&hvtargid=pla-350875853263&psc=1
That driver should work, ad its 5A 12 V, so that's 60 Watts per channel the typical LED strip consumed 4.3 watts per foot. it's also the best solution that works with minimal effort solution.
You can hack of the lead from any suitable 12V power adapter to provide it with the juice it needs and your Apex will natively control it.
(I actually use it to control my moon light that is RGB(true moonlight is really mostly red, just looks blue to us)
If you want to complicate things you can go for Meanwell PWM series drivers that are constant voltage with 3-in-1 dimming
https://www.ledsupply.com/power-supplies/mean-well-pwm-series the PWM-40-12 model should suffice, takes up a lot more space tough.
You are going to use up Three (3) of your VDM ports on your APEX, if you aren't using them for anything cool, if you are, you are going to have to purchase a separate VDM module to gain more ports.
How the ports are wired you can look up on the APEX forums it is on the top in their lighting section.
Seems like a lot of work to integrate this kind of thing in your APEx for something that is purely aesthetics when it comes to lighting.
APEX (VDM Port 1 (channel 1 Red, channel 2 Blue); VDM port 2 (Channel 1 Green, Channel 2 EMPTY (or perhaps it can activate a discoball)))
Remember on LED light strips the common is the positive and each channel is activated using the negative.
Cheers
-Grim
