ZeRO SL MkII with M-Audio Keyrig 49 Midi Controller

Hey there everyone,

I have looked around everywhere and just cannot find an answer to my question. I am looking at buying the ZeRO SL MkII but I am wondering about the external keyboard setup with FL Studio. I have an M-Audio Keyrig 49 Midi controller already so I really don't want to invest in a 25, 49, or 61 key SL MkII as it would be pointless if what i want to do is possible.

I am aware that it is possible to hook up an external keyboard to the ZeRO SL MkII with Ableton but I have not found one forum about making it work with FL Studio. Has anyone else tried it? Even with a different external keyboard? Is it worth it?

Also, I am close to my limit of usb ports on my laptop and was wondering if the ZeRO SL MkII is plugged into my laptop, if I plug my Keyrig into my ZeRO SL MkII via midi, will I also have to also plug it into my laptop via usb? In other words, can I run my external keyboard through the ZeRO SL MkII?

If this is all too much hassle, if you think I should just buy the 49 key SL MkII I will consider it, although in some reviews it is said to be pretty bulky.

Thank you guys so much! And I am extremely sorry if this has already been asked elsewhere or is a stupid question to most of you.