PT 10 + Sibelius 7.5.1 - No transport on ReWire (HELP!)

[catsynth]

Hi all-

I have "successfully" set up Sibelius 7.5.1 in Pro Tools 10 via a ReWire plugin. The plugin is there on an audio track and Sibelius starts up as expected. The Sibelius transport has the little ReWire logo as expected. But the playback in Sibelius won't start. If I start the transport in Pro Tools, Sibelius transport remains off. If I try starting on the Sibelius side, the play button is stuck depressed (though the application remains responsive).

I did find the following log for Sibelius related to ReWire initialization indicating a failure, though unsure the cause. Any help would be appreciated.

Thanks in advance!


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I:2886427328:1912283481:/Users/amanda/Library/Application Support/Avid/Common/SibeliusDevice.log opened on: Sun Oct 11 13:22:19 2015
I:2886427328:1912283521:-------------------------------------------------------------------------------
I:2886427328:1912283528:RWDEFOpenDevice res: 1
I:2953850880:1912309347:Idle() just detected new start req
I:2953850880:1912309389:SibeliusDevice built onec 24 2013
I:2953850880:1912309409:SibeliusDevice::init() in
I:2953850880:1912309748:Writing ReWire lock file: /Users/amanda/Library/Application Support/Avid/Common/sibelius.rewire
I:2953850880:1912310020:SibeliusDevice::init() out
I:2886427328:1913586971:IsPanelAppLaunched: 0
I:2886427328:1913587012:Launch panel app
I:2886427328:1913587020:SibeliusDevice::launchPane l
I:2971422720:1913631405:SibeliusDevice::driveAudio () - IPC shut down, _panelLaunched=false
I:2987397120:1918120250:Client received message
I:2987397120:1918120268:Client received attach request
I:2987397120:1918120275:Client received attach request, process_port not there case
I:2987397120:1918120352:Client received attach request, all shared mem set up
I:2971422720:1918122142ut0 0x1ef29000
I:2971422720:1918122163ut1 0x1ef31000
I:2971422720:1918122295:SibeliusDevice::callback() _panelLaunched=true
E:2971422720:1921458149:Client:rocess mach_msg failed!
I:2971422720:1921458184:Client::detachFromServer in
I:2971422720:1921458201:Client::detachFromServer vm_deallocate in
I:2971422720:1921458226:Client::detachFromServer vm_deallocate out
I:2971422720:1921458249:Client::detachFromServer out
I:2971422720:1921458258:SibeliusDevice::callback() connection failed, _panelLaunched=false
I:2971422720:1954341857:Play mode changed from 0 to 2
I:2971422720:1954363152:Play mode changed from 2 to 1
I:2971422720:1957477932:Play mode changed from 1 to 0