On one computer (a Windows 7 x64 bits), I'm running x64 Blender 2.55 Beta zip:
- a master mode
- a slave mode

On one other computer (Mac OS X Snow Leopard), I'm running Blender 2.55 Beta, Intel:
- a slave

When I launch a rendering to the master (another Windows computer), I get some results, but not all.
I got these messages on the Mac slave:

*** BEGIN CUT HERE ***
Fra:0 Mem:4.14M (9.98M, peak 17.59M) | Network render node initiation
Fra:0 Mem:4.14M (9.98M, peak 17.59M) | Network render connected to master, waiting for jobs
Fra:0 Mem:4.14M (9.98M, peak 17.59M) | Network render processing job from master
Traceback (most recent call last):
File "/Applications/Blender/blender.app/Contents/MacOS/2.55/scripts/io/netrender/client.py", line 203, in render
self.render_slave(scene)
File "/Applications/Blender/blender.app/Contents/MacOS/2.55/scripts/io/netrender/client.py", line 218, in render_slave
slave.render_slave(self, scene.network_render, scene.render.threads)
File "/Applications/Blender/blender.app/Contents/MacOS/2.55/scripts/io/netrender/slave.py", line 153, in render_slave
job_full_path = testFile(conn, job.id, slave_id, job.files[0], JOB_PREFIX)
File "/Applications/Blender/blender.app/Contents/MacOS/2.55/scripts/io/netrender/slave.py", line 79, in testFile
found = os.path.exists(job_full_path)
File "/Applications/Blender/blender.app/Contents/MacOS/2.55/python/lib/python3.1/genericpath.py", line 18, in exists
st = os.stat(path)
TypeError: Can't convert 'tuple' object to str implicitly
Fra:0 Mem:4.14M (9.98M, peak 17.59M) Sce: Ve:0 Fa:0 La:0
Saved: /tmp/0006.png Time: 00:01.94
Fra:0 Mem:4.14M (9.98M, peak 17.59M) | Network render node initiation
Fra:0 Mem:4.14M (9.98M, peak 17.59M) | Network render connected to master, waiting for jobs
Fra:0 Mem:4.14M (9.98M, peak 17.59M) | Network render processing job from master
Traceback (most recent call last):
File "/Applications/Blender/blender.app/Contents/MacOS/2.55/scripts/io/netrender/client.py", line 203, in render
self.render_slave(scene)
File "/Applications/Blender/blender.app/Contents/MacOS/2.55/scripts/io/netrender/client.py", line 218, in render_slave
slave.render_slave(self, scene.network_render, scene.render.threads)
File "/Applications/Blender/blender.app/Contents/MacOS/2.55/scripts/io/netrender/slave.py", line 153, in render_slave
job_full_path = testFile(conn, job.id, slave_id, job.files[0], JOB_PREFIX)
File "/Applications/Blender/blender.app/Contents/MacOS/2.55/scripts/io/netrender/slave.py", line 79, in testFile
found = os.path.exists(job_full_path)
File "/Applications/Blender/blender.app/Contents/MacOS/2.55/python/lib/python3.1/genericpath.py", line 18, in exists
st = os.stat(path)
TypeError: Can't convert 'tuple' object to str implicitly
Fra:0 Mem:4.14M (9.98M, peak 17.59M) Sce: Ve:0 Fa:0 La:0
Saved: /tmp/0007.png Time: 00:01.94
Fra:0 Mem:4.14M (9.98M, peak 17.59M) | Network render node initiation
Fra:0 Mem:4.14M (9.98M, peak 17.59M) | Network render connected to master, waiting for jobs
Fra:0 Mem:4.14M (9.98M, peak 17.59M) | Network render processing job from master
Traceback (most recent call last):
File "/Applications/Blender/blender.app/Contents/MacOS/2.55/scripts/io/netrender/client.py", line 203, in render
self.render_slave(scene)
File "/Applications/Blender/blender.app/Contents/MacOS/2.55/scripts/io/netrender/client.py", line 218, in render_slave
slave.render_slave(self, scene.network_render, scene.render.threads)
File "/Applications/Blender/blender.app/Contents/MacOS/2.55/scripts/io/netrender/slave.py", line 153, in render_slave
job_full_path = testFile(conn, job.id, slave_id, job.files[0], JOB_PREFIX)
File "/Applications/Blender/blender.app/Contents/MacOS/2.55/scripts/io/netrender/slave.py", line 79, in testFile
found = os.path.exists(job_full_path)
File "/Applications/Blender/blender.app/Contents/MacOS/2.55/python/lib/python3.1/genericpath.py", line 18, in exists
st = os.stat(path)
TypeError: Can't convert 'tuple' object to str implicitly
Fra:0 Mem:4.14M (9.98M, peak 17.59M) Sce: Ve:0 Fa:0 La:0
Saved: /tmp/0008.png Time: 00:01.91
Fra:0 Mem:4.14M (9.98M, peak 17.59M) | Network render node initiation
Fra:0 Mem:4.14M (9.98M, peak 17.59M) | Network render connected to master, waiting for jobs
*** END CUR HERE ***

And each time the slave crash, the master don't know it, and try to send jobs to the ghosts slaves, waiting results from these too. So, each crash re-register a new slave to the master, who don't know that the slave is not available.

I join the files master.blend and slave.blend which I use.

The both are run directly form the command line, not from the GUI.