I've a similar board (mine is mx4vr-v01). The image that works for me is the one for "MXQ 4K Pro, RK3228A, DDR3".
Probably you need to replace kernel dtb because in my case the image boots, turn on blue led but freeze with blank screen.
So I've extracted the dtb from my android firmware and used that.
That one is a MXQ 4K (without Pro), so you get RK3228A and DDR2 memories (not DDR3).