This is extremely barebones, you can add stuff to scroll through the receiving history, show the nick and filename, add close button, etc. Open the dialog window with:
/dialog -ma showpic showpic
Put in remotes script:
on *:filercvd:*.bmp,*.jpg,*.gif,*.ico:{ if ($dialog(showpic)) did -g showpic 123 " $+ $filename $+ " }
dialog showpic {
option dbu
title "file received"
size -1 -1 400 320
icon 123,1 1 390 310
}