How can I use "relative knobs"

[Camarada]

HI,

I am trying to control the Mini V with a Keylab49. I set up the knobs in the MiDI Control Center to be relative, so I can use with the same keyboard different Synth Plug ins i.e. I want to use two different Mini V but I want to be able to use the knobs in the "relative " configuration .

Can anybody help me there??

Thanks!!!