SO I was trying to make some use of an older Macbook pro to run my SO3. Tying up one of the other two laptops means I can’t work while the machine is working.
CM4 loads and seemingly connects to my SO3… I was able to home it and jog it around, set my zeroes and load my file. When I clicked START… that was the end of it apparently.
Is this laptop just too old at this point? 
The gcode file was very small… it was just a pocketing operation of 1/16" deep for a 30x30in waste board surfacing.
hmmm…working now. I store my files on my iCloud account so I can save them there from my Windows laptop and access them from the mac. Maybe the gCode file had some issues downloading… or CM4 just crashed. Don’t know.
Still looking for opinions.
Please copy files to a local drive before sending — it shouldn’t be a problem, but it could potentially cause a lag in the sending which could cause a problem.
I use a seriously cr@ptastic atom based tiny little box running win 10, and it seems to be ok. I suspect you’ve got plenty of gumption on an old mac laptop. As @WillAdams says, copy the file locally and that might help with CM. I’ve been using keybase between a mac and a windows box to do this, and it seems to be ok using UGS.
I have been using this older laptop for a few small jobs and it’s been working now. Making sure the file is downloaded rather than residing in the cloud seems to be helping.