Our Electric Paint has a sheet resistance of approximately 55 ohms/square at 50 micron film thickness. If applied using a brush or screen-printed by hand, this decreases to approximately 32 ohms/square.
This means that if you have a square patch of the paint that is 50 microns thick, with any side length, the resistance from one side to the other will be 55 ohms. If you double the length compared to the width, the resistance will also double to 110 ohms. If you halve the length compared to the width, the resistance will halve to 27.5 ohms.
Wikipedia has a great page with further explanation of sheet resistance (and why it is used for materials applied in thin layers) here. There is also more practical information on using the paint in our Application Notes.