Here's a (very simple) lua script with which you can easily record many button presses.
Language: lua
while true do
--set the input you want pressed to 1
--leave everything else as 0
--as the script is running, the input you have set to 1 will be pressed
Y=1
X=0
A=0
B=1
left=0
right=1
up=0
down=0
L=0
R=0
start=0
select=0
--don't touch anything below here
key1={}
if Y==1 then key1.Y=1 end
if X==1 then key1.X=1 end
if A==1 then key1.A=1 end
if B==1 then key1.B=1 end
if left==1 then key1.left=1 end
if right==1 then key1.right=1 end
if up==1 then key1.up=1 end
if down==1 then key1.down=1 end
if L==1 then key1.L=1 end
if R==1 then key1.R=1 end
if start==1 then key1.start=1 end
if select==1 then key1.select=1 end
joypad.set(1,key1)
snes9x.frameadvance()
end
Having some kind of button system is probably better, but until then, hopefully this script can help.