This is a little lengthy, but true gamers will read it all to customize their game...
if you go to the C: Drive under My computer, go to Program files, then go to firefly studios, then go to Stronhold 2, you should see a file called Crests (its 2nd from the top). open it. you should see crest0, crest1, crest2, crest3, crest4, crest5, crest6, crest7, crest8, crest9, and crest10. crest0 is the unowned estate crest. crest1 is your crest in single player. crest2 is the second computers crest. and etc. this will apply for multiplayer, but the other players will not see the customized crests. they will only see the default crests or crest that they customized themselves. if you click on right-click crest0-10, a little box will pop up. in the little box, hit Edit. this should take you to Paint. in paint, you can customize it to just the way you want. then just save it under the same name (Stronghold 2 recognizes crests by name so if u name it something else like Coolest Crest Ever, it will not work and you will most likely be missing a crest, which is NOT cool). That should give you the crest you want. If you want, however, you can delete a crest such as crest3 or something, i dont care which! then go to on of the color choices like green or orange etc. then right-click on the crest you like. hit Copy. go back to the normal crest area. right click anywhere in the crest file area and hit Paste. the just rename it crest3 (OR WHATEVER! ). now go into the game and, WHAMMO! YOU GOT YOURSELF A CUSTOMIZED CREST THINGY!!! OH YEAH!!!!!