CNC Machining Oneshop Redding (router problems)

Today, when I got to Oneshop the router for the CNC machine, wouldn't turn on, the light would come on indicating that it has power, just the tool wouldn't spin. Was looking around thinking maybe a cord came loose or something of the sort, but nothing was loose. I asked Tyler (oneshop owner) about it and he said the brushes on the motor top may have worn down sufficiently to need to be replaced. Thankfully he had a couple of extra which I installed and that got it working again without a hitch.

After starting up another cut of Kevin (small circular paperweight) it started without issue and ran through about 80% of its path before it suddenly stopped moving. This was a bit annoying and I had noticed it doing the same with another cut. After posting this on Instagram, my brother mentioned having the same issue and that the solution was to lower the tolerance from its default 0.004in to something rougher and just create a new toolpath to clean it up afterward to get a cleaner finish. The reason it does that is the computer has to calculate each layer and multiplies over and over to the point where it overloads and crashes. I believe this is just an issue with this specific machine though I haven't tried it on the larger one they have.