It's an interesting learning curve. If you are just interested in learning how to read the data, you can download the program and instructions provided by @h-elsner following this link:
"Altitude and crash problem"
If you have a specific issue and need help, you can zip up the entire "FlightLog" directory from the SD card under the battery in the ST12, and upload the zip to the forum. The members here will try to help you. It is important that you provide as much information as you can related to the problem to help interpret the readings.