I loaded up some cloud credit and launched a node from the panel in blender. It appeared in the node list, I gave it full weight (wanted to see how it handled my scene that would take 16 hours to render on 3 laptops networked, to estimate and stuff).
After some fiddling, it showed ready then synced. I started a still render to start, render failed. I checked the log, it showed several sync failures (node still shows synced in the panel) I repeated this a dozen times, testing render animation as well.
I used suggestions from the forum such as saving and reloading, repeatedly. I burned some compute credits in idle time trying to figure it out and gave up and shut the node down for now.
The behavior seems to be that it shows as synced until a render job comes, then it rapidly fails to sync. I didn't realize I could save the log to disk until it had removed itself from the node list and I was testing with a few local nodes to make sure it was working at all, but it reported no specific error other than failing to sync and render failed. Blender v2.81a Crowd Render v0.2.2
For others finding this topic: The problem appears to be that I was running an Eevee project, which is not supported by CR's cloud offering
3MB is not too large, if you can send the file to info at crowdrender dot com dot au that would be great :)
Blend file is about 3MB
As far as I know, not huge. I'm using no external textures that would need baked, just shaders and emitters - there may be high geometry etc I'm not an expert (let alone in optimizing 3D) Where should I send a copy to investigate?
Oh dear, that shouldn't happen. How large is your project? We can take a look and see what the problem is by loading your project here and checking for errors.