Sometimes the AI captures your portal flag or at least made your flag yellow. You seemed to ignore this for some time although you had nothing better to do than recapture it. That is bad. If your own portal flag has been captured then it has a very high priority to repcapture it as fast as possible. Otherwise the enemy creeps will put pressure on your defense towers.
i'll remember to recapture my portal flags if they're being captured / half way done .
Talking about Portals. At the end of the game you have not tried to caputure the portals of the enemys. This is bad. If you have bought Catapults and later Giants it is very good to take this portals. Then your creeps will be very close to the citadel and you have more or less won the game. If you are not suprior (like I was or you were in the end) it is also very helpful to capture the enemy portal flag and then put a flag lock on it and then try to caputre the other portal flag.
I seem to have forgotten about it >.>alright then . capture enemy portal flags asap when attacking citadel .
At the end you bought everything up to Catapults and then giants. Although you had enough money you did not buyed the other upgrades like armor or additional attack strenght for the creeps. When you have some spare money at the end buy that citatdel upgrades. The stronger your creeps get the better for the final attack at the citadel.
i was saving some money for some stuffs . i think .. anyway, i should be buying cats and giants after i get all my items ? or until i get enough money to afford them ?
At the end you saved to much money. Sometimes you had more than 25000 gold. In such a case I would have bought All Fathers Ring. There is no point in having 20000 or more gold but do not buy anything with it. Better buy "cheap" artefacts and replace your normal items with them. This will let you make more and faster kills so you get that gold back quickly.
is all fathers ring no good ?
I would recomend to have at least one teleport scroll I you have a spare place. They are cheap and sometimes very helpful.
noted ! infact, i can use this teleport scroll to tp to my portal flag if i'm far away to recapture it 
I have never played such a Regulus build you have done. Though I am not sure if your items were always the best you could choose. For example you had no items for a long time that increased the attack speed. As you had Angelic Fury as only attack I would have recommended such items. I think also that Nature's Reckoning is no good choice. I would suggest Unbreakable Boots for the same price. There you get also HP and HP regen while the other only has some low chance of some damage.
a low chance of armour ignoring damage + high attack speed = higher chance ? >.>
anyway, this build was found on demigod wikia so yeah ..
Are AA builds no good ? is having high armour good against AA builds ? what about burst damage e.g. a fire TB ? is armour good against them ?
You put much gold into items to increase your HP and often made melee. This worked against these demigods but Regulus is not a good melee Demigod. With him you usually do more kind of hit and run, especially as you had fully upgraded your range skill. Against other demigods like UB you can easily get into trouble when you engage them in melee if you not have a decent level and/or item advantage.
i should be increasing my speed because i'm supposed to be a hit and run huh ? alright then . i'll buy my items accordingly to what i'm playing my DG as .
edit: uploaded my 2nd win . is it better now ?
p.s. there were a few times i stood there and did nothing . was kinda at a lost for what to do lol .
http://www.gamereplays.org/demigod/replays.php?game=51&tab=upcoming&show=details&id=103775&st=0#post6686108