I think any MIDI controller will be fine with BIAB; just specify it as the input MIDI device in Opt, Pref, MIDI Drivers.

I have an E-Mu Xboard 25 on a test system I use. It measures just under 18" wide, and 9.5 inches deep, so it fits right in front of the screen with no problem. It is two octaves, C to C, but you can easily shift octaves with the Octave Transpose + and - buttons. It also works on Windows 7 using the Vista drivers. It is powered just by USB, has a power supply input jack if you prefer, and has a MIDI Out port. You can send MIDI either by USB or MIDI Out.

I don't play keyboard so I don't benefit from the fact it also has a feature called weighted keys, but a real player would want that feature.

BIAB 2025 Win Audiophile. Software: Studio One 7 Pro, Swam horns, Acoustica-7, Notion 6, Song Master Pro, Win 11 Home. Hardware: Intel i9, 32 Gb; Roland Integra-7, Presonus 192 & Faderport 8, Royer 121, Adam Sub8 & Neumann 120 monitors.