installation of openwrt on access point

Hello, i'm looking for some assistance in installing a support version of openwrt onto an access point, its running this chipset (Mediatek AP-MT7621A) which says it is supported, but i'm getting some issue keeping the http open long enough for me to upload the image, shows briefly then goes away, also my icmp drop after a few pings upon a restart. I've not worked with WRT much before but would like to test if I can get this working. fun project!! :)