Rpg Maker Developers Group

I am working for a climb animation for my character where she would grab a key to open the door. The key is located on top of something, so I made this climb animation. I use Stepping Animation and Change Image in movement route event.

The problem is, there is a glitch shown in the first attempt of the action. In the second action, there is no glitch. I can't spot the root cause for the past several days. Is there something I am missing?
Do you have suggestion for the best method to animate player activities such as climb, grab, push/pull object, dance maybe, etc (Kan Gao's latest game, Impostor Factory, has that detail animations for every activity. What approach does he use?). I am afraid that I am not in the best practice.

Here is the detail:
The Glitch:

Climb sprites (I use 5 different files since the default can only read 3 columns per file, I have 15 columns):


Event: