Head to the plugin menu and download OScam ymod which is at Menu > Plugins > Download Plugins (green) > Softcams > OScam ymod > yes - I suggest this version of OScam as this one has all the configuration files pre-configured for you.
Once downloaded now activate the softcam in the menu at Menu > Setup > SoftCam / CI > Softcam Manager > Enable Startup (blue) (so it will auto start after a reboot) then OK so it actually starts OScam right now. Once done you can now exit this menu and you will be able to access the OScam Webif at
http://ip-address-of-receiver:8888 and can change the various settings from here.
I personally would recommend using the webif to change the settings you want rather than physically swap the oscam files over as this can lead to problems, but if you'd prefer to do that or are more confident doing it that way then you can FTP into the receiver and you'll find all the OScam ymod configuration files in /etc/tuxbox/config/
Default FTP username is root and password is blank (i.e. no password).
For channel settings personally I would always use AutoBouquetMaker if it's for 28.2 East, depends what you want you want to use this with of course, but if you want to use AutoBouquetMaker then first make sure your tuners are configured correctly at Menu > Setup > Service searching > Tuner configuration - It's important to get this right especially with the two DVB-S/S2 tuners, so if you have say only a single 28.2 East feed then set the tuner up as that and not as though you have two feeds, if it is really two feeds than that's fine, set it up as that - this becomes important to get right later on for using AutoBouquetMaker and CrossEPG.
Once you are happy the tuners are configured correctly you can then head to AutoBouquetMaker at enu > Setup > Service searching > AutoBouquetMaker and first choose your Provider and region, then green to OK before going to Start scan. If all has been configured correctly then is a minute or two you if should indicate it's found the channel settings and once complete it will return to its own menu At this point you can exit this and all menus then when back to normal TV press the up arrown on the remote control, press green for Satellites then blue for Favourites and if all went to plan you should have all your 28.2 East bouquets scanned in as per the region you chose and be ready to view!