It doesn't seem like a good way but it's all I can think of. Do something like this on init and then if s isn't in the modes it sets disable the box. Idk.
mode $chan +abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ $str(1 $+ $chr(32),52)

You might already know this but you can use

on *:Dialog:CMM:*:*: {
if ($devent == sclick) {
if ($did == #) { }
if ($did == #) { }
}
}

Also you have 2 Topic locks, 19 and 23 I think. Oh and unless it's different for different networks +s is secret not +S shrug