HELP with a game... please

Hello!
I’m doing a little game for a school project.There are some major bugs to the game at the moment. Can someone help me please?
I have the following issues at the moment:

-The character stops at different positions on the y-axis when touching the ground. Is there a simple and understandable actionscript that can fix this problem?

-I’ve also attached a second game file where I try to fix the climbing problem. I want the character to be stuck to the ladder when letting go off the up or down button instead of falling down. I also wonder why the character is still stuck when climbing to the right, above the second table (platform)?