The liquid that is stored in the cap is Potassium Chloride (KCL). It tends to crystalize once it leas out tof the probe. The crystals are non-hazardous substances. Sometimes traveling from place to place the storage cap can loosen up and some of the KCL can leak. In most cases, the meter would not have any problem because of that. What you can do is just wipe them off with a tissue and keep the spear probe stored in the solution. It is a necessity to store the spear probe in the KCL solution because it can be permanently damaged if stored dry.
There is a very small chance that your meter could be damaged, as the only way it is possible is if the KCL got inside the meter and soaked the circuit board. The best way to check for this is to unscrew the probe from the meter and turn the probe upside down to see if any liquids are running into the circuit board. If it happens you should call the Apera Instruments Customer Service to discuss how we can solve the problem.