[Other] Movement script problem

[Frownyface77]

ROM: FireRed

The script is supposed to activate when stepping on a "Script event" (In advanced map editor) but instead, freezes the game when stepping on it, and nothing happens (have to restart ROM). Here it is: (It deletes my #dyn 740000 when I save, idk why)

#org 0x81666FE
'-----------------------------------
lockall
checkflag 0x7304
if true jump 0x80B4F77 ' Flag is set
applymovement 0x3 0x83B5E9D ' walk_down walk_down ...
pauseevent 0x0
message 0x83B51A1 ' \n\h01!\nWho told yo...
callstd MSG_LOCK ' Built-in lock command
message 0x8740BA1 ' The good old\nSNORLA...
callstd MSG_LOCK ' Built-in lock command
message 0x8740CC2 ' MISTY uses water-typ...
callstd MSG_LOCK ' Built-in lock command
applymovement 0x3 0x83B5EA5 ' walk_up walk_left wa...
pauseevent 0x0
disappear 0x3
setflag 0x7304
releaseall
end

#org 0x80B4F77
'-----------------------------------
release
end


#org 0x83B51A1
= \n\h01!\nWho told you to come here?\pWell, anyway, now that\nyou're here,\pI've got another mission for you.\p\v\h06 and a few other TEAM ROCKET\nmembers are busy taking control of CELADON CITY,\pand I just finished closing off the\nNORTH and WEST entrypoints for\pCERULEAN CITY, to prepare for our raid.

#org 0x8740BA1
= The good old\nSNORLAX-in-the-road. Classic.\pHere's where you come in.\nGYM LEADER MISTY is the\ponly one here who\ncould stop us.\pDefeat her, and we own CERULEAN CITY!\nNot the best, but we'll take it.\pI like your potential, kid.\nIf you pull this off, I'll make sure\pto mention you to GIOVANI.

#org 0x8740CC2
= MISTY uses water-type.\nI think I saw an ODDISH\pin the tall grass back on\nROUTE 5.\pGood luck, AGENT \v\h01.

#org 0x83B5E9D
M walk_down walk_down walk_down walk_right walk_right walk_right walk_down end

#org 0x83B5EA5
M walk_up walk_left walk_left walk_left walk_up walk_up walk_up walk_up end