Yep, I been at work. sorry 'bout that. hehe. I can't really answer a lot of questions yet, but I can say these things:
Yes, this is 100% my FPGA design here and it is not one of the other SNES cores.
It runs all custom chip carts, super gameboy (1 and 2), game saver+ (lol), even tested a doctor sf disk based thinger, and the sd2snes is what I used during dev so that works great as well. I tested the Sufami Turbo and that works as well. Basically it runs every single thing I can stuff into the cart slot. I did a lot of testing with dozens of carts and all the various add-on devices I have and could find. I have not tested the MSU-1 but since the SD2SNES itself works 100%, I don't see why this won't work either. I will try it soon just to confirm. Audio input on the cart slot is supported and that's mainly what it adds.
There's a completely new scaler designed specifically for this (vs. the nt mini's) and I spent a lot of time to make sure video output is the best it can be. It's still zero lag like before or you can have the fully buffered experience like on the framemeister.
Yes it does do deinterlacing so RPM racing works as well as the menu screens and such that use that.
There is a cool blending mode so i.e. Jurassic Park's overlays and Kirby's Dreamland 3 look great (you can turn that on/off) too. Scanlines were improved and gamma correction is in there if you prefer it to have that CRTish look.
Yes, it uses the Cyclone V similar to the mini but it's the A4 version instead of the A2 so lots more resources! (yeay)
I tested all the SNES peripherals except the light gun, and they work fine including multitaps, the mouse, etc.