There may be a bug in the software which in my case causes a crash if multiple processes are used and not 'ordered' by layer / height in the processes window.
I use a Prusa i3 Mk3, which at the moment can print infill acceptably very fast (>150mm/s PLA, and I'm doing 75mm/s PETG) but get's ringing and generally less tidy if perimeters are anywhere near that, so I'm down closer to 40mm/s for perimeters. At the same time fast PETG infill on the first layer does not stick at such high speeds, so I have to use a separate process for the first layer to adjust speeds accordingly - if I just use a % slowdown to drag the first layer infill speed down to acceptable numbers then perimeters are sloooooow.
With that in mind I would create the main process, then copy it, slow the speeds (And do some X/Y size adjustment for 'elephants foot') and set the start and stop heights. If I then click 'Prepare to Print' I get a crash every time, which loses the plate layout and processes on restart, going back to the last factory file save. If I reorder the processes by dragging and dropping so that the 'copy' process (First layer) is above the main process it works fine.
I'm getting into the habit of reordering where necessary or using the variable settings wizard which also works fine but it doesn't seem right that the process order in the window (Even if start and stop heights are set correctly) causes a software-exit crash with lost data.