Table 1. Troubleshooting.

Step	Problem	Possible cause	Solution
1.1	Fibrous contaminants on grid films	If the edge of the filter paper is not smooth and clean, it may spread fibrous contaminants to the suspension when touching it	Take a new piece of filter paper, gently fold it and use the folding edge to blot the grid
2.1	The temperature of the sample stage cannot be stabilised at 93 K (–180 °C)	The liquid nitrogen inflow is not stable or not sufficiently strong and the temperature of the cryo chamber is consequently not stabilised	Adjust the pressure of the liquid nitrogen pump to a moderate level
2.4	The sample falls out of focus during video acquisition	The temperature of the sample stage is not stabilised so a noticeable mechanical drift occurs	Stabilise the temperature (see above)
		Unspecified environmental disturbances destabilise the stage	Terminate the acquisition, refocus by adjusting stage Z and restart the acquisition
2.6	Error report	The entire folder of the program package is not added to the path	Add the entire folder, including all of the subfolders, to the path before running the main2.m script
		CUDA is not properly installed	Reinstall the CUDA Toolkit