This will sync Reaper to Biab's play/stop/position.

Download midiOut vst http://www.thepiz.org/plugins/?p=midiOut

Copy to Macintosh HDD/Library/Audio/Plug-Ins/VST

Load the midiOut vst into a midi track.

Create a virtual midi cable:
1.Launch the "Audio/Midi Setup" of OS X.
2.Open the "Window" menu and click on "Show MIDI Window"
3.Double-click on the IAC Driver icon.
4.Activate the "Device is online" checkbox.
5.You can rename the Device Name if you like, but please only use characters that are available on an English keyboard!

In the midiOut vst select the virtual midi cable.

In Reaper Preferences - Audio - Midi Devices - Input, Enable+Control your Virtual midi cable.
Reaper, right click Play button, Use Input > SPP "Your Virtual midi cable"
Check "Enable synchronization to timecode" (uncheck to use Reaper normally)
Press Play button so it's Green and waiting for Biab sync.

Reaper will follow Biab play/stop/position (the Mac version of midiOut vst won't Loop a section as it has no MTC out).

In Biab Edit - SongForm - Unfold

Save As Button > Video, Custom Dimensions, size 640x360, check Scroll Ahead, Ok Render

Drag Biab Song.M4V into a track in Reaper, turn volume down but don't mute.

Reaper View - Video window.

Just drag n drop from Biab to Reaper via Drop.







Reaper right click Play button: