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When running materials that print hotter (PC, CF-Nylon, etc.) I find that I have to turn down the flow rate and/or temperature a bit. You have a pool of melted material in the print head that is under pressure from the filament feeding into into it. So if your temp is too high you can end up over-extruding quite a bit and then dragging the print head through the still soft/molten plastic (especially on smaller parts). Over time that will build up and can grab the entire part and break it loose from the print bed, leading to "flooding" of the print head - which is what it looks like was starting to happen to your print head. Since the feeder gears are so far away from the print head a retraction does not instantaneously relieve the pressure on that pool of liquid plastic so you have to fine tune the temp. and flow to allow for good layer adhesion, but not end up with over-extrusion.
