Hi mjr! You'r pm is full ... I understand that I'm a member only too, only 10 messages 
Anyways, I will put the message here. Hope it dosn't bother anyone!!
Sorry about the full mailbox - I need to clean up a bit!
These are good questions that might well be of interest to other people, so I'm actually kind of glad you posted them here. 
I'm in the process of buying all the stuff I need, the board, the slide potentiometer and the ledwiz alternative list of things. I have one ledwiz, but it's already full with the implementation I want to do, but with this I can add more things without buying another ledwiz ... right? Can I have this for extra toys too? Will not interfere?
Right. That's exactly what I'm doing and it works great. The DOF guys even made things easy by adding a "KL25Z" option on their list that automatically selects unit #8, which is what the Pinscape software uses by default.
The one thing to keep in mind is that the KL25Z only has 10 PWM-capable outputs. If you're still in the planning stages, just make a list of which devices need PWM and which don't, and attach the PWM items (all or as many as possible) to the LedWiz. PWM is for anything that needs dimming or speed control - basically anything with an LED or a motor. You don't need PWM for contactors, solenoids, knockers, beacons, strobes, bells, chimes. It's also not necessary for any of the front-panel buttons if you have lights in them (Start, Exit, Extra Ball, Launch Ball, Coin In, Menu, Info, etc), since those lights are just on or off.
I haven't touched DOF so I don't know how everything works or integrate in VP...
(noob here)
Do you have a more illustrated picture or diagram of a fully loaded ledwiz implementation?
It's not too hard to get everything running with VP. The DOF site has pretty clear installation instructions: http://directoutput....stallation.html.
I'll try to put together a block diagram of my wiring. Every setup is unique, so you probably won't want to duplicate my setup exactly, but my setup is probably fairly typical.
Btw, the mosfets in mouser (they offer one of the best services around the word btw, not the cheapest, but quality items and great service) ... I found that the mosfet you link in the tutorial are in backourder (only 1 available) ... and was wondering.. why that in specific? Are there any other alternative? What specs I have to look for? I think this is an acceptable replacement right? http://www.mouser.pr...BUK95150-55A127
There's definitely nothing special about the specific MOSFETs I listed - lots of others will work just fine. The only reason I have such specific part numbers in there is that I've had the experience myself of finding a nice circuit design on the Internet that only has vague indications of what parts to use, so I end up spending hours hunting around for the right parts - I just wanted to make this as plug-and-play as possible.
The one your found - the BUK95150-55A127 - looks good to me. The circuit in the build guide should actually work with a really wide range of MOSFETs. It provides about +6V to the MOSFET gate, which I think should make it usable with practically any power MOSFET that I've seen. Anything where the data sheet says it's good for switching applications will probably work.
The one you found can handle 55V at 13A, which is plenty of power handling for anything in a virtual pin cab. The most power-guzzling device in my cab is probably the gear motor, which draws about 4A steady state, so 13A should be very safe. I personally like having this stuff over-designed so that nothing gets hot. 
Good luck with the project!