You want something like this ¿?
local image = fe.add_image("[!plnum]", 50, 50, 100, 100)
function plnum( index_offset ) {
local ex = regexp(@"(\d+)P(?: (alt|sim))?");
local plinfo= fe.game_info( Info.Players, index_offset ).tolower()
if ( plinfo.len() >= 1 ) {
local plex = ex.capture(plinfo);
local plnum = plinfo.slice(plex[1].begin,plex[1].end);
return plnum + ".png"
} else {
return "players-unknown.png"
}
}