Speaking of how to lock your frame properly - this is how I usually do it, the front lock usually locked against the railing as well as the frame & wheels if one is presented;
Also, always try and fill in as much space as you can when locking the rear lock, less movement, no room for any tools to be inserted, etc. it's almost impossible to try and wiggle that lock as it's pretty much stuck solid;
Speaking of how to lock your frame properly - this is how I usually do it, the front lock usually locked against the railing as well as the frame & wheels if one is presented;
Also, always try and fill in as much space as you can when locking the rear lock, less movement, no room for any tools to be inserted, etc. it's almost impossible to try and wiggle that lock as it's pretty much stuck solid;